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PubMed1996

Mycoplasmal pneumonia in pigs in Croatia: first evaluation of a vaccine in fattening pigs.

The immunoprophylaxis of mycoplasmal pneumonia of swine (MPS) caused by Mycoplasma hypopneumoniae was investigated for the first time in fattening pigs in Croatia. The incidence of MPS was monitored in pigs weighing on average 27.5 kg (12 weeks old) after immunization with a M. hyopneumoniae vaccine. Of 350 pigs in each group, in the nonvaccinated group 55 animals (15.7%) were affected by pneumonia and 11 (3.1%) died of consequences of pneumonia, whereas in the vaccinated group 20 pigs (5.7%) were affected by pneumonia without any death due to the infection. In the nonvaccinated group 44% more pigs were individually treated with antibiotic, and these animals received in-feed therapy for more than 1/4 of the fattening period. Vaccinated pigs gained weight faster, at the rate of 0.745 kg/day (or 82 g/day more) than control animals. The mean score of lung lesions due to M. hyopneumoniae was 10.51 in the control pigs and only 0.54 in the vaccinated animals. The total tissue alterations on lungs due to M. hyopneumoniae, Pasteurella multocida and/or Actinobacillus pleuropneumoniae expressed as the mean-score were 13.21 in the control group and 2.98 in the vaccinated group. According to the results of evaluation of the M. hyopneumoniae vaccine in the field, the vaccine appeared to provide an adequate immunity in fattening pigs but was less effective when administered to younger pigs at 1-3 weeks of age.

Animals↗

PubMed1990

The inhibition of [3H]leukotriene D4 binding to guinea-pig lung membranes. The correlation of binding affinity with activity on the guinea-pig ileum.

Guinea-pig lung membranes contain high affinity (KD = 0.8 nM) binding sites for [3H]leukotriene D4 [( 3H]LTD4). The binding is inhibited by leukotriene antagonists, such as ICI 198615 and SK&F 104353, in a manner consistent with the Law of Mass Action at a single site. It is also inhibited by a range of leukotriene analogues in a dose-related manner. Inhibition by some of these e.g. LTC4 suggests that the [3H]LTD4 binding sites are heterogeneous. The binding affinity of the leukotriene analogues is significantly correlated (P less than 0.001) to their spasmogenic activity on guinea-pig ileum but not on guinea-pig lung strip. The binding affinity of the leukotriene antagonists is also correlated to their antagonist activity on guinea-pig ileum (P less than 0.05) but not on guinea-pig lung. These results indicate that the [3H]LTD4 binding site in guinea-pig lung is similar to the leukotriene receptor activated by LTD4 and LTE4 on guinea-pig ileum. The contractile response of guinea-pig lung strips to leukotrienes, in the presence of indomethacin, is mediated by a distinct type of leukotriene receptor.

Animals↗

PubMed1988

The distribution of melanin-concentrating hormone-like immunoreactivity in the central nervous system of rat, guinea-pig, pig and man.

The distribution of melanin-concentrating hormone-like immunoreactivity was investigated by radioimmunoassay in the CNS of rat, guinea-pig, pig and man. Highest concentrations of melanin-concentrating hormone-like immunoreactivity were found in the hypothalamus of all the species: rat 204.4 +/- 14.9; guinea-pig 159.5 +/- 23.3; pig 10.9 +/- 4.5 and man 80.1 +/- 19.1 pmol/g. Gel chromatographic analysis of hypothalamic extracts showed five immunoreactive peaks of melanin-concentrating hormone-like immunoreactivity in the rat and pig and six in the guinea-pig and man. High-performance liquid chromatography analysis of hypothalamic extracts showed five immunoreactive peaks in rat, guinea-pig, pig and four in man. However, these peaks appeared at different retention times from that of the single peak of salmon melanin-concentrating hormone. Examination of subcellular fractions of whole rat brain showed that most of the melanin-concentrating hormone-like immunoreactivity is found in the synaptosome fraction. Stimulation of melanin-concentrating hormone-like immunoreactivity release from rat hypothalamic slices revealed that potassium in the presence of calcium stimulated melanin-concentrating hormone-like immunoreactivity release. These findings suggest that mammalian melanin-concentrating hormone-like immunoreactivity has a different amino acid sequence from salmon melanin-concentrating hormone and may exist in multiple molecular forms. It is possible that melanin-concentrating hormone may play a role as a neurotransmitter or modulator in the mammalian CNS.

Adult↗

PubMed2006

Absorption of the nerve agent VX (O-ethyl-S-[2(di-isopropylamino)ethyl] methyl phosphonothioate) through pig, human and guinea pig skin in vitro.

The physico-chemical properties of VX make the skin the most likely route of absorption into the human body. The development of effective medical countermeasures against such percutaneous threat agents relies on the use of appropriate animal models, as the inherent toxicity of nerve agents precludes the use of human volunteers. Previous studies have characterised the mechanism of nerve agent toxicity in rodent models, however, it is generally accepted that one of the most appropriate animal models for human skin absorption is the domestic pig. The purpose of the present study was to measure and compare the skin absorption kinetics of VX in vitro using pig, human and guinea pig skin to highlight any potential species differences in skin permeability. When undiluted VX was applied directly to the skin, the permeability of guinea pig skin was approximately 7-fold greater than human skin. There was no significant difference in the permeability of pig and human skin. When VX diluted with isopropyl alcohol was applied to the skin, the permeability of guinea pig skin was approximately 4-fold greater than human skin. There was no significant difference in the permeability of pig and human skin. From this data it may be inferred that dermatomed, abdominal pig skin is an appropriate model for the human skin absorption of VX.

Adult↗

PubMed2002

Different responses to drugs against overactive bladder in detrusor muscle of pig, guinea pig and mouse.

Direct comparison of experimental data for drugs commonly used in the treatment of overactive bladder is difficult because of possible species differences. In this study, we compare the effects of atropine, propiverine, oxybutynin and tolterodine in strips of pig, guinea pig and mouse detrusor muscle. In the three species, we observed slight differences in potency of carbachol-induced biphasic contractile responses between the species (guinea pig>pig>mouse). Cumulative concentration-response curves for carbachol were shifted to the right by atropine, propiverine, oxybutynin and tolterodine. However, at higher concentrations of the latter three antagonists, the maximum response to carbachol was also reduced. Therefore, propiverine, oxybutynin and tolterodine must have additional pharmacological actions beyond competitive antagonism at muscarinic receptors. Electric field stimulation (30 Hz) of detrusor strips led to contraction amplitudes, which remained constant over time (210 min) in pig, decreased by 17+/-5% in guinea pig, and increased by 28+/-9% in mouse detrusor muscle. Electric field stimulation-evoked contractions were suppressed to 18% of pre-drug control by high concentrations of atropine (10 microM) in pig, but to a much lesser extent in guinea pig and mouse (to 46% and 70%, respectively). In all three species, a myogenic component of contraction was observed in the presence of tetrodotoxin (1 microM). Compared to atropine, the bladder spasmolytic agents propiverine, oxybutynin and tolterodine also reduced electrically evoked contractions in the three species, though higher concentrations were required. The differences in the reported effects of the spasmolytic agents commonly used for treating overactive bladder suggest that drug action is strongly dependent on the species. Thus, a comparison of drug effects is only feasible in the same animal model and the results cannot easily be transferred to humans.

Animals↗

PubMed1998

Rilmenidine reveals differences in the pharmacological characteristics of prejunctional alpha2-adrenoceptors in the guinea-pig, rat and pig.

1. The alpha2A and alpha2D-adrenoceptor subtypes are thought to be species homologs most easily differentiated on the basis of the potency of antagonists. In the present study we have compared the effect of rilmenidine with two other selective alpha2-adrenoceptor agonists, UK-14304 (5-bromo-6- [2-imidazolin-2-ylamino]-quinoxaline) and clonidine, against electrically-evoked contractions in five isolated preparations from the rat, guinea-pig and pig, and, where possible, determined the receptor subtype involved. 2. UK-14034, clonidine and rilmenidine produced concentration-dependent inhibition of the electrically-evoked contractions of the rat isolated vas deferens and tail artery and the guinea-pig ileum. These inhibitory effects were reversed by the selective alpha2-adrenoceptor antagonist, RX-811058 (1 microM), except in the rat tail artery preparations where the remaining neurogenic response was inhibited; evidence for the involvement of 'innervated' alpha2-adrenoceptors. Both clonidine and UK-14304 produced concentration-dependent inhibition of responses in the porcine isolated tail artery and urinary bladder but clonidine was markedly less efficacious in these preparations. In contrast, rilmenidine failed to inhibit the neurogenic contractions in either preparation. 3. Although rilmenidine failed to elicit a detectable response in either the porcine isolated tail artery or urinary bladder, it (10 microM and 30 microM, respectively) competitively antagonised the inhibitory effects of UK-14304 with an estimated dissociation constant of (pK(B)) 5.82 and 5.93, respectively. 4. Prazosin (1 microM) failed to alter the effect of UK-14304 against neurogenic contractions in the porcine isolated urinary bladder, while rauwolscine (pK(B) 8.87) was 10 fold more potent than phentolamine (pK(B) 7.56). On the other hand, phentolamine (pK(B) 8.42) was only marginally more potent than rauwolscine (pK 8.05) against clonidine-induced inhibition of electrically-evoked contractions of the guinea-pig isolated ileum. This pharmacological evidence with antagonists supports the presence of alpha2D-adrenoceptors in the rat and guinea-pig and the alpha2A-adrenoceptors in the pig. 5. We have demonstrated that rilmenidine, unlike clonidine and UK-14304, is devoid of any agonist activity at prejunctional alpha2A-adrenoceptors in the pig, but is an efficacious agonist at alpha2D-adrenoceptors in the rat and guinea-pig.

Adrenergic alpha-2 Receptor Agonists↗

PubMed2004

Effects of artificial obstruction on the function of the upper urinary tract of Guinea pigs, rats and pigs.

PURPOSE: Four different experiments in animals were performed to evaluate the influence of pyelo-ureteral surgery on the function of the upper urinary tract. METHODS: Experiment I: In 17 female guinea pigs pyelo-ureteral anastomosis was performed microsurgically. Three months later, the ureteral peristalsis was investigated by measuring the intraureteral pressure and the in vitro activity of the renal pelvic and ureteric wall was analysed. Experiment II: 10 rats were used for microsurgical uretero-ureteral anastomosis. One month after surgery the pyelo-ureteral peristalsis was examined by videomicroscopy while simultaneously measuring the renal pelvic and intravesical pressure. Subsequently the kidneys were removed for histological examination. Experiment III: In 2 pigs unilateral pyeloplasty was performed. Using an implanted transmitter the intravesical and the renal pelvic pressures were recorded continuously over a time interval of 3 months. Five months after surgery the pyelo-ureteral peristalsis was investigated by pyelography. The kidneys were then removed for histological and biomechanical examinations. Experiment IV: A partial artificial obstruction was performed in 16 guinea pigs by implanting the ureter into the psoas muscle. Two to six months following surgery their upper urinary tracts were removed for analysis of in vitro activity as well as histological and immunohistochemical investigations of the ureter and renal pelvis. RESULTS: Experiment I: Ultrasound investigation showed in all cases a significant dilation of the renal pelvis. The ureteral contraction frequency distally was decreased in vivo as well as in vitro (p <0.05) compared with the controls. Experiment II: Videomicroscopic imaging showed in eight out of nine cases an interruption of the peristaltic wave below the anastomosis; the ureteral peristalsis was restored distally by ureteral contractions with a decreased frequency. Retroperistalsis was seen in the lower part of the ureter. The frequency of renal pelvic and ureteral contractions were decreased (p <0.05). Renal pelvic baseline pressure as well as contraction amplitude were irregularly changed. Histological examinations showed increased connective tissue within the renal pelvic wall in all cases. Experiment III: In both pigs an intermittent change in contraction frequency of the renal pelvis was found, associated with a changing contraction amplitude. Five months after surgery an interruption of the peristaltic wave was detected in both pigs. Histological examinations showed increased connective tissue within the renal pelvic wall. The stiffness of caliceal and pelvic tissue was lower following the pyeloplasty compared to the controls. Experiment IV: Following artificial partial ureteral obstruction in all guinea pigs the in vitro investigations showed an increased spontaneous activity of the upper urinary tract except in the proximal part of the ureter. Ureteral obstruction produced a change in contraction pattern of the proximal ureter and a decrease in contraction frequency of the distal ureter. Immunohistochemical investigations revealed rarefication and disorientation of nerve fibres within the proximal ureteric wall. CONCLUSIONS: Surgical interruption of the ureteral continuity and re-anastomosis cause a temporary disruption of the peristaltic wave at the anastomosis site. Ureteral peristalsis is restored by ureteral contractions associated with retroperistalsis as well as a decreased contraction frequency. Uretero-ureteral anastomosis in rats, pyelo-ureteral anastomosis in guinea pigs and pyeloplasty in pigs seem to influence the upper urinary tract similarly to a chronical functional obstruction, causing changes in pyelo-ureteral motility and spontaneous muscular activity of the renal pelvic and ureteral wall as well as biomechanical and histological characteristics.

Anastomosis, Surgical↗

PubMed2000

In vitro alpha-adrenoceptor autoradiography of the urethra and urinary bladder of the female pig, cat, guinea-pig and rat.

OBJECTIVE: The aim of this study was to investigate the distribution of alpha1- and alpha2-adrenoceptors in the urethra and urinary bladder of the female pig, cat, guinea-pig and rat. MATERIALS AND METHODS: The binding distributions of an alpha1-adrenoceptor ligand (3H-prazosin) and an alpha2-adrenoceptor ligand (3H-rauwolscine) were determined using in vitro autoradiography. Autoradiograms were analysed by combining computer-based image analysis and light microscopy. RESULTS: In the pig, guinea-pig and rat urethra 3H-prazosin binding was highest in the muscle layer. In the cat urethra 3H-prazosin binding could not be analysed due to a negative chemography artefact. In the pig, cat and guinea-pig urethra 3H-rauwolscine binding was highest in the urothelium, followed by the sub-mucosa, with low levels in muscle. Little 3H-rauwolscine binding was observed in the rat urethra. In the urinary bladder of all species 3H-prazosin binding was low. In the rat bladder, binding was higher in the trigone than in the dome. In the pig, cat and guinea-pig bladder 3H-rauwolscine binding was highest in the mucosa. with little binding in muscle or lamina propria. In the rat bladder, there was little binding and no regional differences. CONCLUSIONS: Alpha1-adrenoceptors were predominantly located in urethral smooth muscle, indicating their contractile importance in maintaining continence. Alpha2-Adrenoceptors were present in the urethral submucosa and bladder mucosa, but not in muscle, suggesting a role in regulation of blood flow, urethral lubrication and tumescence, but not in contraction.

Adrenergic alpha-Antagonists↗

PubMed1953

Regression of transplanted lymphomas induced in vivo by means of normal guinea pig serum. II. Studies on the nature of the active serum constituent: histological mechanism of the regression: tests for effects of guinea pig serum on lymphoma cells in vitro: discussion.

In an extension of the experimental studies recorded in an associated paper; attempts were made to isolate and characterize the constituent of guinea pig serum responsible for inducing regression of transplanted lymphomas in vivo. The active material was precipitated readily from the whole serum, along with some of the globulins, by means of ammonium sulfate in concentrations of 2.0 molar or greater; it withstood heating at 56 degrees C. for 20 or 30 minutes, but was inactivated upon heating at 66 degrees C. for similar periods; it was completely inactivated by chymotrypsin in concentrations of 1 or 2 mg./cc. during 6 hours at 37 degrees C. Furthermore, the inhibitory effects of small amounts of the guinea pig serum in vivo were enhanced upon admixture with immune sera prepared by injecting the lymphosarcoma cells into rabbits. The facts as a whole suggest that the active material is a protein, and that it may be one or another of the components of complement; yet they do not suffice to establish its identity. Microscopic studies showed that the cells of subcutaneous lymphomas rapidly died and were resorbed following injections of relatively large amounts of guinea pig serum intraperitoneally into mice carrying them, while similar changes followed more gradually after repeated injections of smaller amounts of guinea pig serum. No changes referable to the guinea pig serum were seen in the normal tissues or organs of mice receiving it. Mouse lymphoma cells, suspended artificially as individuals in a physiological saline solution, regularly remained viable following incubation in vitro in mixture with guinea pig serum during 6 hours at 37 degrees C. The finding provides strong evidence that the regression of lymphomas that follows injection of guinea pig serum in vivo is brought about through some reaction in which the guinea pig serum and the host both participate. Some of the implications of the findings are discussed.

Animals↗

PubMed1985

A more sensitive enzyme immunoassay of anti-insulin IgG in guinea pig serum with less non-specific binding of normal guinea pig IgG.

An enzyme immunoassay of anti-insulin IgG in guinea pig serum was improved in sensitivity by reducing the non-specific binding of normal guinea pig IgG and enhancing the specific binding of anti-insulin IgG. Silicone rubber pieces or polystyrene balls were coated with normal rabbit IgG, followed by coupling of insulin using glutaraldehyde. The insulin-normal rabbit IgG-coated silicone rubber pieces or polystyrene balls were incubated with normal rabbit IgG and then with diluted guinea pig anti-insulin serum in the presence of normal rabbit IgG at a lower temperature (20 degrees C). Finally, the solid phases were incubated with rabbit (anti-guinea pig IgG) Fab'-horseradish peroxidase conjugate to measure the amount of guinea pig IgG bound. The detection limit of anti-insulin IgG in guinea pig serum was improved 10 to 100-fold compared to that of enzyme immunoassay performed by incubating insulin-bovine serum albumin-coated solid phases with diluted guinea pig anti-insulin serum at 37 degrees C and then with rabbit (anti-guinea pig IgG) Fab' conjugated to beta-D-galactosidase from Escherichia coli, according to a previous report (Kato, K., et al. (1978) J. Biochem. 84, 93-102).

Animals↗

PubMed1988

Evidence for adenosine triphosphate as an excitatory transmitter in guinea-pig, rabbit and pig urinary bladder.

1. The effects of alpha,beta-methylene ATP (alpha,beta-MeATP) on membrane properties and excitatory junction potentials (EJPs) were examined in smooth muscle cells of the guinea-pig, rabbit and pig bladder. 2. Intracellular recording with microelectrodes was used to record membrane electrical activity from the guinea-pig bladder. ATP (10(-3) M) produced a rapid, large depolarization with a marked increase in spike frequency, while carbachol (10(-4) M) or acetylcholine (ACh; 10(-4) M) produced only a small or no depolarization with a smaller increase in spike frequency. alpha,beta-MeATP produced a similar response to that of ATP but at a much lower concentration (5 x 10(-6) M), and the response was transient even in the continuous presence of this agent. 3. Changes in the membrane potential and conductance elicited by alpha,beta-MeATP were also measured with the double sucrose-gap method. alpha,beta-MeATP (5 x 10(-6) M) depolarized the membrane and increased the membrane conductance in all three species, but both parameters returned to control values during continuous exposure to this agent. 4. Intracellular recording with microelectrodes showed that in the guinea-pig bladder treatment with alpha,beta-MeATP abolished the response to ATP, while the response to ACh was unchanged. 5. With the double sucrose-gap method, EJPs were elicited by transmural nerve stimulation of strips of the guinea-pig, rabbit and pig bladder and had spikes superimposed, leading to contractions. Desensitization of P2-purinoceptors by alpha,beta-MeATP (3-5 x 10(-6) M) abolished the EJPs and spikes, and reduced the contraction. Atropine (10(-6) M) alone did not alter the EJPs but reduced the contraction. Combined application of both agents abolished the contraction. 6. It is concluded that in the guinea-pig, rabbit and pig bladder ATP is an excitatory transmitter with ACh and EJPs are mediated by ATP.

Acetylcholine↗

PubMed1993

Protective effect of dihydroheptaprenol in combination with vaccine to experimental Actinobacillus pleuropneumoniae infection in guinea pigs and pigs.

We investigated the effects of dihydroheptaprenol (DHP) on resistance of guinea pigs and pigs inoculated with Actinobacillus pleuropneumoniae (Apn) vaccine to subsequent challenge with Apn. Guinea pigs with complement-fixation (CF) antibody titers of 1:8 and 1:16 after intramuscular (i.m.) inoculation with inactivated Apn vaccine showed enhanced resistance to intraperitoneal (i.p.) infection with a homologous Apn strain (5 x 10(10) CFU/animal) when injected with DHP (20 mg/kg, i.m.) on the day before infection. The survival rates of the control, vehicle (lecithin solution without DHP), and DHP groups were 33%, 37%, and 63%, respectively, and that of the DHP group was significantly higher than the rates of the other groups (P < 0.05). Pigs with CF antibody titers of 1:8 and 1:16 after i.m. inoculation with inactivated Apn vaccine showed enhanced resistance to intratracheal infection with 5 x 10(10) CFU of Apn when injected with DHP (1, 2.5, or 5 mg/kg, i.m.) on the day before infection. The survival rates of the control, vehicle, DHP 1 mg/kg, DHP 2.5 mg/kg, and DHP 5 mg/kg groups were 37%, 38%, 47%, 60%, and 73%, respectively, and pigs given DHP at a dose of 5 mg/kg showed a significantly higher survival rate than the vaccinated control pigs (P < 0.05). The protective effect of DHP in vaccinated guinea pigs and pigs suggests that phagocytosis and bactericidal activity may be enhanced by this agent, depending on some opsonification effect on Apn antibody.

Actinobacillus Infections↗

PubMed1975

Calcium uptake and calcium release by subcellular fractions of smooth muscle. II. Kinetics of calcium uptake by microsomes and mitochondria from pig coronary artery and guinea pig ileum.

Calcium uptake by the microsomal and mitochondrial fractions of pig coronary artery and guinea pig ileum was studied in the presence of ATP, ATP plus oxalate and without ATP and oxalate. Microsomes and mitochondria of both smooth muscles were found to be unable to accumulate appreciable amounts of calcium in the absence of ATP. Oxalate noticeably stimulated the calcium uptake of the mitochondrial fraction from pig coronary artery but had little effect on calcium uptake by the microsomal fraction of this smooth muscle. The calcium uptake of microsomes and mitochondria from guinea pig ileum was not or only slightly enhanced by oxalate. There are typical kinetics regarding the time course and the extent of calcium uptake by microsomes and mitochondria from pig coronary artery and guinea pig ileum. In comparison, considerable qualitative and quantitative differences between both smooth muscles are observed. The high ATP-dependent calcium uptake capacity of the mitochondria from pig coronary artery and guinea pig ileum are a further argument for the hypothesis that these organelles may play an important role in the contraction-relaxation mechanism of smooth muscle.

Adenosine Triphosphate↗

PubMed1985

Patterns of K/N ratios with growth of guinea pig, beagle, and pig.

The influence of age on patterns of K/N ratios (mEq/g) for fat-free whole body organs and tissues was analyzed for the guinea pig, ages 1 to 80 days (82 to 849 g); for the pig, 0 to 89 days (151 to 33,650); and for the beagle, 0 to 383 days (252 to 13,065 g). Strong correlations existed between total K, total N, and fat-free wet weight (FFWW). Mean whole body K/N ratios were 2.57 +/- 0.241 for guinea pigs, 2.53 +/- 0.50 for pigs, and 1.79 +/- 0.27 for beagles. Increase in body weight of the beagle and of the components, skeletal muscle and nonmuscle (whole animal minus skeletal muscle), were divisible into two statistically significant periods: the first from 0 to 62 days, the second from 63 to 383 days. For the first period, the K/N ratio for the whole animal was 1.70 +/- 0.33, for nonmuscle was 1.61 +/- 0.34, and for skeletal muscle was 2.08 +/- 0.50; for the second period, the values were 1.93 +/- 0.22, 1.25 +/- 0.18, and 2.82 +/- 0.83, respectively. Mean K/N ratios of organs and tissues of the pig and beagle differed significantly from mean whole body K/N ratios, with the exception of liver for the beagle and miscellaneous for the pig. Patterns of K/N ratios during increases in FFWW were species-specific for total body as well as for various tissues and organs. As FFWW increased, the whole body K/N ratio did not change significantly in the guinea pig, but decreased significantly in the pig because of the decreased ratio for skeletal muscle. As FFWW of the beagle increased in the first growth period, the slope for the whole body K/N ratio did not differ statistically from zero, although the mean measured ratio increased significantly for liver and skeletal muscle. This increase was counter-balanced by a statistically significant decrease in ratios for skin and skeleton. FFWW continued to increase in the second growth period and the whole body K/N ratio increased, primarily the result of significantly increased ratios for liver and skeletal muscle.(ABSTRACT TRUNCATED AT 400 WORDS)

Age Factors↗

PubMed1993

Identification of pig chromosomes in pig-mouse somatic cell hybrid bivariate flow karyotypes.

To identify pig chromosomes in pig-mouse somatic cell hybrids, dual-laser flow karyotypes and GTG-banded metaphase spreads of pig, mouse, and 7 pig-mouse hybrid cell lines were compared. Pig chromosomes no. 1, 2, 5, 6, 10, 11, 13, 14, 16, 18, X and Y were tentatively assigned to individual peaks in the pig flow karyotype on the basis of DNA content vs. relative chromosome length. In the 7 hybrid cell lines, 7 out of 8 peaks distinct from those of the mouse cell line could be correlated with the presence of pig chromosomes no. 5, 9, 10, 11 or 16, 14, 15, and 18, whereas 1 peak appeared to correspond to the presence of 1 middle-size chromosome (3, 4, or 7). Other pig chromosomes present in the hybrids could not be detected with certainty due to superposition with mouse peaks and mouse chromosome rearrangements.

Animals↗

PubMed2006

Transmission of mitochondrial DNA in pigs and progeny derived from nuclear transfer of Meishan pig fibroblast cells.

In embryos derived by nuclear transfer (NT), fusion, or injection of donor cells with recipient oocytes caused mitochondrial heteroplasmy. Previous studies have reported varying patterns of mitochondrial DNA (mtDNA) transmission in cloned calves. Here, we examined the transmission of mtDNA from NT pigs to their progeny. NT pigs were created by microinjection of Meishan pig fetal fibroblast nuclei into enucleated oocytes (maternal Landrace background). Transmission of donor cell (Meishan) mtDNA was analyzed using 4 NT pigs and 25 of their progeny by PCR-mediated single-strand conformation polymorphism (PCR-SSCP) analysis, PCR-RFLP, and a specific PCR to detect Meishan mtDNA single nucleotide polymorphisms (SNP-PCR). In the blood and hair root of NT pigs, donor mtDNAs were not detected by PCR-SSCP and PCR-RFLP, but detected by SNP-PCR. These results indicated that donor mtDNAs comprised between 0.1% and 1% of total mtDNA. Only one of the progeny exhibited heteroplasmy with donor cell mtDNA populations, ranging from 0% to 44% in selected tissues. Additionally, other progeny of the same heteroplasmic founder pig were analyzed, and 89% (16/18) harbored donor cell mtDNA populations. The proportion of donor mtDNA was significantly higher in liver (12.9 +/- 8.3%) than in spleen (5.0 +/- 3.9%), ear (6.7 +/- 5.3%), and blood (5.8 +/- 3.7%) (P < 0.01). These results demonstrated that donor mtDNAs in NT pigs could be transmitted to progeny. Moreover, once heteroplasmy was transmitted to progeny of NT-derived pigs, it appears that the introduced mitochondrial populations become fixed and maternally-derived heteroplasmy was more readily maintained in subsequent generations.

Animals↗

PubMed1994

Characterization of pig-mink cell hybrids: assignment of the TK1 and UMPH2 genes to pig chromosome 12.

By fusion of thymidine kinase-deficient mink cells with pig leukocytes, a new type of cell hybrid was produced. It was demonstrated that pig chromosomes segregate in pig-mink hybrids and that hybrid cells contain no cytologically visible rearrangements between the chromosomes of parental species, or chromosome fragmentation. With a set of subclones of two primary hybrid clones, the genes for thymidine kinase-1 (TK1) and uridine 5'-monophosphate hydrolase-2 (UMPH2) were assigned to pig Chromosome (Chr) 12. A cell line with a single pig Chr 8 on the background of mink chromosomes was established. This clone could serve as a source of DNA for building a chromosome-specific library of pig Chr 8. The data obtained suggest that pig-mink cell hybrids can be used for mapping of pig chromosomes.

5'-Nucleotidase↗

PubMed1982

Effect of carbon monoxide on atherogenesis in normal pigs and pigs with von Willebrand's disease.

The extent of coronary and aortic atherosclerosis was examined in pigs following balloon-catheter injury of coronary arteries and subsequent feeding of an atherogenic diet for 4 months. The pigs were either exposed intermittently to 100 ppm carbon monoxide or to ambient air alone. Three types of pigs were used: normals, homozygotes for von Willebrand's disease (bleeders), and heterozygotes (carriers). The 3 types of pigs developed coronary artery intimal lesions of similar thickness. Aortic lesions, quantified as percent of aortic surface involved with sudanophilia and raised fibrous plaques, were slightly less extensive in bleeder pigs than in normals. Carbon monoxide exposure did not increase the thickness of coronary artery intimal lesions, nor did it increase the percent of aortic surface involved with sudanophilia or raised fibrous lesions. These results suggest that exposure to low levels of carbon monoxide does not perceptibly enhance atherogenesis induced by hypercholesterolemia. None of 14 bleeder pigs showed evidence of myocardial infarction, despite significant coronary artery narrowing. Of the 24 normal and carrier pigs, 5 showed myocardial infarction. Four of these 5 pigs were exposed to carbon monoxide, while 1 was not exposed. These findings suggest that exposure to low levels of carbon monoxide may increase the incidence of myocardial infarction and that the absence of von Willebrand factor may be protective.

Animals↗