SEARCH · PubMed Health

Results for “Tissue Distribution”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 793 records · Page 44Linked to original sources

PubMed2005

Tissue distribution and ontogeny of mouse organic anion transporting polypeptides (Oatps).

Organic anion-transporting polypeptides (Oatps) are Na(+)-independent solute carriers for cellular uptake of organic compounds. The purpose of this study is to determine 1) the constitutive mRNA expression of the 15 mouse Oatp genes in 12 tissues, 2) whether there are gender differences in Oatp expression, and 3) the ontogenic expression of Oatps in liver and kidney. The mRNA expression of the 15 mouse Oatps was quantified using the branched DNA technique. Oatp1a1, 1a4, 1b2, and 2b1 are expressed in liver at relatively high levels, with Oatp1b2 being exclusively expressed in liver. Oatp1a1, 1a6, 3a1, and 4c1 are highly expressed in kidney. Oatp1a4 and 1c1 are highly expressed in brain. Oatp1a5, 6b1, 6c1, and 6d1 are predominant in testes. Oatp2a1, 4a1, and 5a1 are predominantly expressed in placenta. In liver, expression of Oatp1a1 was male-predominant, whereas expression of Oatp1a4 and 1a6 was female-predominant. In kidney, expression of Oatp1a1, 3a1, and 4c1 was higher in males than in females. Hepatic expression of Oatp1a1, 1a4, 1a6, 1b2, and 2b1 gradually increased after birth and reached adult levels by 6 weeks of age. Only Oatp2a1 was expressed at adult levels at birth. In kidney, expression of mouse Oatp1a1, 1a6, and 3a1 was lower at birth than at 6 weeks of age, whereas expression of mouse Oatp1a4, 2a1, and 2b1 was similar at birth and at 6 weeks of age. These data on the tissue distribution and ontogenic expression of mouse Oatps will aid in understanding the pharmacokinetics and toxicokinetics of drugs and other chemicals.

Animals↗

PubMed1983

Synthesis, tissue distribution and tumor uptake of [99Tc]tetrasulfophthalocyanine.

99Tc-labeled-tetrasulfophthalocyanine was prepared by the condensing of sulfophthalic acid and pertechnetate in the presence of a reducing agent. Reaction products were purified in various chromatographic systems and characterized by combustion, specific activity and spectral analyses. The tissue distribution pattern of the major product was studied in tumor-bearing rats. Most of the activity accumulated in the liver, kidneys, ovaries and uterus, whereas tumor uptake mainly occurred in the exterior cell layers. The in vivo stability of the complex was evidenced by the absence of 99Tc accumulation in the thyroid and the stomach.

Adenocarcinoma↗

PubMed1999

Tissue distribution of placenta-type 6-phosphofructo- 2-kinase/fructose-2,6-bisphosphatase.

Several isozymes of 6-phosphofructo-2-kinase/fructose-2, 6-bisphosphatase have been characterized from mammalian tissues and, based on tissue origin, they are classified as liver, skeletal muscle, heart, testis, and placenta isozymes. In this paper, we examined the tissue distribution of placenta-type isozyme in rat tissues at the levels of transcription and translation. Analysis by Northern blotting showed that placenta, brain, testis, liver, kidney, and skeletal muscle expressed mRNA of placenta-type isozyme. Western blot analysis of fractions from POROS-HQ column chromatography of extracts from various rat tissues showed that proteins of placenta-type isozyme are expressed in placenta, brain, testis, liver, spleen, heart and lung, but not in kidney and skeletal muscle. An immunohistochemical study showed that, in liver, placenta-type isozyme is localized in Kupffer cells. These results indicate that isozymes of this particular enzyme may occur in particular cell types within each tissue.

Animals↗

PubMed1992

In vitro release, pharmacokinetic and tissue distribution studies of doxorubicin hydrochloride (Adriamycin HCl) encapsulated in lipiodolized w/o emulsions and w/o/w multiple emulsions.

The lipiodolized w/o emulsion or w/o/w multiple emulsion containing Doxorubicin hydrochloride (1; Adriamycin HCl) with different emulsifiers was prepared to evaluate in vitro sustained-release behavior, pharmacokinetic and tissue distribution function in Sprague Dawley (SD) rats. The results of dissolution indicate that the release of 1 was significantly sustained for both emulsions when HCO-60 (polyoxyethylene (60) hydrogenated castor oil) was used as an emulsifier. The serum concentration of 1 was reduced and prolonged for both emulsions with the increase of HCO-60. The C(max) level was lowered and T(max) value was delayed after administration of w/o emulsions with higher HCO-60 concentration. The apparent terminal half-life for 1 released from some emulsions with higher concentration of HCO-60 was 3-folds higher than that of the 1 solution. The clearance of some w/o or w/o/w ADR emulsions also decreased with the increase of HCO-60. Not only the concentration of 1 in heart and kidney decreased significantly after the administration of w/o emulsions with the higher concentration of HCO-60, but also the hepatic concentration of 1 was higher and increased with HCO-60 concentration. The hepatic 1 level became lower after administration of w/o/w multiple emulsions with the increase of HCO-60; however, the concentration of 1 in heart, lung and spleen increased somewhat. The results indicate that lipiodol and HCO-60 seemed to play an important role in the prolongation and selective retention of w/o emulsion or w/o/w multiple emulsion, in vitro and in vivo.

Animals↗

PubMed2002

Isolation and differential tissue distribution of two human cDNAs encoding PDE1 splice variants.

A cDNA selection technique has been used to isolate full-length human cDNAs of the phosphodiesterase 1 (PDE1) calcium calmodulin (CaM)-regulated phosphodiesterase gene family. We isolated cDNAs representing multiple splice variants of PDE1A, 1B and 1C from a variety of tissues. Included among these were two novel splice variants for PDE1A and 1B. The first, PDE1A5, encodes a 519-residue protein, which is different from PDE1A1 by the insertion of 14 residues, a divergent carboxy terminus and also differs from PDE1A3 through a divergent amino terminus. Our second novel splice variant represents the first occurrence of a splice variant of the PDE1B gene. PDE1B2 encodes a 516-residue protein and diverges from PDE1B1 by the replacement of the first 38 residues by an alternative 18, which is predicted to be functionally significant. Using the splice variant sequence differences to perform comparative Northern analysis, we have demonstrated that each variant has a differential tissue distribution.

Alternative Splicing↗

PubMed1998

Supplementation with canthaxanthin affects plasma and tissue distribution of alpha- and gamma-tocopherols in mice.

The effects of oral doses of canthaxanthin on tissue distribution of alpha- and gamma-tocopherols were investigated in three experiments in male and female Balb/c mice. Mice were assigned to receive canthaxanthin [7 or 14 microg/(g body weight.d)] or placebo (olive oil) by gavage for different periods of time (0, 1, 2, 4 and 6 wk). A 2 wk-treatment with canthaxanthin resulted in incorporation of the carotenoid in all tissues analyzed, including liver, spleen, kidney, lung and heart. In liver, the maximum accumulation of the carotenoid was reached after 2 wk of dosing in female mice and after 6 wk in male mice. Canthaxanthin incorporation was accompanied by changes in alpha- and gamma-tocopherol concentrations in plasma and tissues. These included the following: 1) a significant increase (P < 0.001) in alpha-tocopherol concentration in spleen (21 and 27% in male and female mice, respectively) after 2 wk and in liver ( approximately 50% in both male and female mice) after 6 wk; 2) a significant decrease in gamma-tocopherol concentration in plasma (P < 0.05) and tissues (P < 0.001) after 2 wk of treatment. In female mice, this decrease was 55% in plasma, 43% in liver, 44% in kidney, 71% in lung and 70% in heart. In male mice, the decrease was observed only in plasma (30%), kidney (54%) and heart (46%). In liver, the decrease in gamma-tocopherol concentration was both dose- and time-dependent and significantly (P < 0.001) greater in female than in male mice. We conclude that dietary administration of canthaxanthin modifies tocopherol status in murine tissues.

Animals↗

PubMedDate not supplied

[Obesity and adipose tissue distribution in men: relation to sex steroids and insulin].

The aim of this study was to assess the correlation between the distribution of adipose tissue, sexual hormones and hyperinsulinemia in male obesity. Fifty-two obese males, aged 40.0 +/- 10.9 years old and with a body mass index (BMI) of 35.0 +/- 6.1 (m +/- SD), not suffering from diabetes or any other endocrine disease, were included in the study. A group of 20 subjects aged 30.5 +/- 7.9 (p less than 0.005 vs obese subjects) and with a BMI of 23.0 +/- 2.0 were used as controls. Body fat distribution was assessed using the waist/hip ratio (w/h ratio): 0.985 +/- 0.052 in obese subjects and 0.913 +/- 0.061 in controls (p less than 0.005). In comparison to control subjects, significantly lower levels of total (T) (357 +/- 132 vs 498 +/- 142 ng/dl; p less than 0.005) and free testosterone (FT) (14.2 +/- 2.9 vs 17.1 +/- 2.6 pg/ml; p less than 0.05) were found in the obese group, as well sex hormone binding globulin (SHBG) (41.7 +/- 31.9 vs 66.2 +/- 18.6 nmol/l; p less than 0.001). None of the other steroids (androstenedione, dehydroepiandrosterone-sulphate, estrone, 17 beta-estradiol, dihydrotestosterone) or FSH and LH gonadotropins assayed differed between the two groups. Significantly higher levels of insulin and C-peptide, both fasting and after a oral glucose tolerance test, were also found in obese subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗

PubMed1991

Two high affinity binding sites for pituitary adenylate cyclase-activating polypeptide have different tissue distributions.

Two bioactive products of pituitary adenylate cyclase-activating polypeptide (PACAP) prohormone have been isolated from ovine hypothalamus: PACAP38 with 38 residues and PACAP27 corresponding to the N-terminal 27 residues of PACAP38. Immunocytochemical and RIA results support the existence of PACAP in the rat brain, posterior pituitary, and various peripheral tissues. Furthermore, high affinity PACAP-binding sites have been detected in the rat brain, anterior pituitary, and cultured astrocytes which differ from those in lung, liver, and cultured mouse splenocytes. In the present study additional rat tissues were examined to elucidate the location and characteristics of PACAP-binding sites using [125I] PACAP27 with conventional methods of receptor autoradiography and RRA. Binding specificity was established by displacement with unlabeled PACAP27 or a related peptide, vasoactive intestinal polypeptide (VIP). PACAP27-binding sites were localized autoradiographically in the testis, epididymis, adrenal gland, lung, liver, prostate gland, and seminal vesicle; binding sites were not detected in the heart, kidney, or thymus. In the testis and epididymis, a PACAP27-binding site was localized on germinal cells and in the adrenal gland on medullary chromaffin cells. Excess VIP did not displace PACAP27 binding localized in these three tissues. A site with a greater affinity for PACAP27 than for VIP was detected in adrenal gland and epididymis, characteristic of a site recognized previously in hypothalamus, anterior pituitary, and cultured astrocytes. The PACAP-specific site was more abundant in these tissues than a second site to which PACAP27 and VIP bound with similar affinities. Accordingly, the first site has been named type I. In lung, liver, prostate, and seminal vesicle, VIP displaced PACAP27 binding localized autoradiographically. Lung and liver contained an abundant site to which PACAP27 and VIP bound with similar affinities. This binding site, measured previously in lung, liver, and cultured splenocytes, may be shared by PACAP and VIP and has been named type II. Taken together, these data support the existence of two high affinity binding sites for PACAP with different tissue distribution.

Adrenal Glands↗

PubMedDate not supplied

Quantifying the 'appleness' or 'pearness' of the human body by subcutaneous adipose tissue distribution.

To quantify subcutaneous adipose tissue topography (SAT-Top) describing individual SAT distribution for a subject or even a group we measured subcutaneous adipose tissue thickness at 15 specified body sites of 303 healthy women aged 20-69 yrs and 20 women with proven non-insulin-dependent diabetes mellitus (NIDDM) by the optical device 'LIPOMETER'. The type of upper-body- and lower-body-fat pattern, (apples or pears), was determined by factor analysis of the data. Upper body sites were highly loaded in factor 1, whereas factor 2 included highly loaded body sites from the lower extremities. For an individual, factor 1 scores > factor 2 scores, was described as an 'apple'-type, while factor 2 > factor 1 was described as a 'pear'-type. We found about 80% 'pears' and 20% 'apples' in 20-29 year olds and 20% 'pears' and 80% 'apples' in 60-69 year old women. Women with NIDDM tended to be 'super-apples'. SAT-Top provides a useful differentiation between apples and pears and we recommend this approach as a screening method.

Adipose Tissue↗

PubMed1991

Tissue distribution of amphotericin B lipid complex in laboratory animals.

Amphotericin B lipid complex (ABLC), under development for the treatment of serious fungal disease, is not a true liposome but a complex of amphotericin B, dimyristoyl phosphatidylcholine and dimyristoyl phosphatidylglycerol with a particle size range of 1.6-6.0 microns. Tissue distribution of ABLC was determined in mice and rats after i.v. or i.p. administration. ABLC resembles typical liposomal preparations with amphotericin B concentrating in the reticuloendothelial system. After a single i.v. treatment with ABLC, amphotericin B was present in high concentrations in liver, lung and spleen of mice and rats while plasma levels were consistently low. Mouse liver contained 48% of the administered dose 1 h after treatment and always contained the largest amount of amphotericin B after ABLC treatment. In mice treated once daily for 7 consecutive days with 10 mg kg-1 ABLC, liver amphotericin B concentration reached 377 micrograms g-1. Tissue concentrations of amphotericin B were substantially lower when ABLC was given i.p. instead of i.v. with reticuloendothelial tissues containing 2- to 7-fold more after i.v. treatment. Animals treated with 10 mg kg-1 ABLC for 14 consecutive days showed no overt signs of toxicity and had only transient changes in liver and kidney function after treatment.

Amphotericin B↗

PubMed2005

Acrylamide tissue distribution and genotoxic effects in a common viral infection in mice.

Acrylamide (AA) has been shown to cause neurotoxic effects in humans and neurotoxic, genotoxic, reproductive, and carcinogenic effects in laboratory animals. Infection with the human coxsackievirus B3 (CB3) in the murine model results in changed uptake and tissue distribution of several environmental pollutants, which may result in aggravated disease. In the present study female Balb/c mice were infected with CB3, and on day 1 of the infection, dosed orally with approximately 50 microg/kg bw of [(14)C]acrylamide ((14)AA) and subsequently sacrificed on day 3 of the infection for studies of the distribution of radioactivity and genotoxic effects in terms of the frequency of micronucleated erythrocytes. Infected mice developed an expected clinical signs of disease. The infection decreased the radioactivity by 45% (p<0.05) in the pancreas but increased it by 70% (p<0.05) in the blood and more than two-fold in the thymus (p<0.01). However, the infection caused no changes in the radioactivity in the brain, heart, liver, lungs, spleen, or kidneys. As a response to the infection the proportion of young red blood cells (PCE) decreased to about a third (p<0.001) of that in the control mice, but no genotoxic effects were observed. Thus, the tissue radioactivity after (14)AA administration indicated an infection-induced change in the metabolism of AA, the exact pathogenic interpretation of which warrants further studies.

Acrylamide↗

PubMed1999

Tissue distribution of silibinin, the major active constituent of silymarin, in mice and its association with enhancement of phase II enzymes: implications in cancer chemoprevention.

Polyphenolic antioxidants are being identified as cancer preventive agents. Recent studies in our laboratory have identified and defined the cancer preventive and anticarcinogenic potential of a polyphenolic flavonoid antioxidant, silymarin (isolated from milk thistle). More recent studies by us found that these effects of silymarin are due to the major active constituent, silibinin, present therein. Here, studies are done in mice to determine the distribution and conjugate formation of systemically administered silibinin in liver, lung, stomach, skin, prostate and pancreas. Additional studies were then performed to assess the effect of orally administered silibinin on phase II enzyme activity in liver, lung, stomach, skin and small bowel. For tissue distribution studies, SENCAR mice were starved for 24 h, orally fed with silibinin (50 mg/kg dose) and killed after 0.5, 1, 2, 3, 4 and 8 h. The desired tissues were collected, homogenized and parts of the homogenates were extracted with butanol:methanol followed by HPLC analysis. The column eluates were detected by UV followed by electrochemical detection. The remaining homogenates were digested with sulfatase and beta-glucuronidase followed by analysis and quantification. Peak levels of free silibinin were observed at 0.5 h after administration in liver, lung, stomach and pancreas, accounting for 8.8 +/- 1.6, 4. 3 +/- 0.8, 123 +/- 21 and 5.8 +/- 1.1 (mean +/- SD) microg silibinin/g tissue, respectively. In the case of skin and prostate, the peak levels of silibinin were 1.4 +/- 0.5 and 2.5 +/- 0.4, respectively, and were achieved 1 h after administration. With regard to sulfate and beta-glucuronidate conjugates of silibinin, other than lung and stomach showing peak levels at 0.5 h, all other tissues showed peak levels at 1 h after silibinin administration. The levels of both free and conjugated silibinin declined after 0.5 or 1 h in an exponential fashion with an elimination half-life (t((1/2))) of 57-127 min for free and 45-94 min for conjugated silibinin in different tissues. In the studies examining the effect of silibinin on phase II enzymes, oral feeding of silibinin at doses of 100 and 200 mg/kg/day showed a moderate to highly significant (P < 0.1-0.001, Student's t-test) increase in both glutathione S-transferase and quinone reductase activities in liver, lung, stomach, skin and small bowel in a dose- and time-dependent manner. Taken together, the results of the present study clearly demonstrate the bioavailability of and phase II enzyme induction by systemically administered silibinin in different tissues, including skin, where silymarin has been shown to be a strong cancer chemopreventive agent, and suggest further studies to assess the cancer preventive and anticarcinogenic effects of silibinin in different cancer models.

Animals↗

PubMed1996

Dosimetry of radionuclide therapy using radiophosphonated antisense oligodeoxynucleotide phosphorothioates based on animal pharmacokinetic and tissue distribution data.

The aim of this study was to evaluate the therapeutic possibilities of radiolabeled antisense oligodeoxynucleotides. The internal radiation dose from known cellular and animal data was calculated, and the suitability of different phosphorus isotopes as labels for oligonucleotides was assessed. We calculated the pharmacokinetics and tissue distribution in vivo of short oligodeoxynucleotide phosphorothioates by using the data from two different radionuclides: phosphorus-33 (t1/2 = 24.4 days, maximum beta-energy = 250 ke V) and phosphorus-32 (t1/2 = 14.3 days, maximum beta-energy = 2270 ke V). The absorbed doses of 32P-labeled and 33P-labeled oligonucleotides were estimated using the published biodistribution data for several oligonucleotides in animal models for both tumor xenografts and AIDS. The local absorption of 33P was higher than that of 32P if the radius of the spherical distribution of activity was smaller than approximately 500 microns. In a mouse tumor xenograft model, an intravenously injected activity of 1 MBq achieved sufficient radiation doses in the tumor; 11 Gy for 32P and 1.5 Gy for 33P were obtained. In normal organs in the same model, the liver doses were 5.0 Gy (32P) and 0.7 Gy (33P), and the kidney doses were 14 Gy (32P) and 2.0 Gy (33P). We conclude that 33P may have more beneficial radiotherapeutic characteristics for oligonucleotides than 32P. This method could be applied on the macroscopic, cellular, and subcellular levels and help to design further experimental studies for the use of oligonucleotide radiotherapy and phosphorothioate probes.

Acquired Immunodeficiency Syndrome↗

PubMed1976

Tissue distribution and mode of DNA methylation in mice by methyl methanesulphonate and N-methyl-N' -nitro-N-nitrosoguanidine: lack of thymic lymphoma induction and low extent of methylation of target tissue DNA at 0-6 of guanine.

The methylating agents methyl methanesulphonate (MMS) and N-methyl N'-nitro-N-nitrosoguanidine (MNNG), administered by single i.p. injection in mice failed to yield thymic lymphoma at doses around 60% of the LD50 values, in contrast to MNUA which gives a high yield of tumours by this route. Comparison of the tissue distribution and mode of DNA methylation by these agents showed a positive correlation with ability to methylate the 0-6 atom of guanine in DNA of the target tissues thymus and bone marrow and tumorigeneis. MMS gave a low yield of this product due to its relatively low Sn1 reactivity but was able to methylate DNA extensively at other sites in the target tissues and other organs examined. MNNG despite its ability to methylate 0-6 of guanine in DNA in vitro to the same relative extent as the potent carcinogen MNUA, methylated DNA of thymus and bone marrow to a very small extent in vivo but was able to methylate DNA in certain other tissues nearer the site of i.p. injection. These findings contrast with the general relatively extensive methylation of 0-6 of guanine in DNA of the target tissues and other organs by N-methyl-N-nitrosourea (MNUA).

Animals↗

PubMed1987

The rabbit differs from other mammalian in the tissue distribution of alkaline phosphatase isoenzymes.

There are only two gene loci code for alkaline phosphatase of mammalian other than human and great apes: one for the intestinal form and other for the liver/kidney/bone form. The former form is present only in the intestine and the latter form occurs in other tissues such as liver, kidney and bone. In the present study, the rabbit was found to be different from other mammalian in the tissue distribution of alkaline phosphatase isoenzymes: only in the rabbit, most of the enzyme in the kidney and liver was the third form which differs from the liver/kidney/bone form, and this form was enzymatically and immunologically similar to the intestinal form of ALPase.

Alkaline Phosphatase↗

PubMed1994

Pharmacokinetic and tissue distribution studies of the photosensitizer bis(di-isobutyl octadecylsiloxy)silicon 2,3-naphthalocyanine (isoBOSINC) in normal and tumor-bearing rats.

Bis(di-isobutyl octadecylsiloxy)silicon 2,3-naphthalocyanine (isoBOSINC) is a representative of a group of naphthalocyanine derivatives with spectral and photophysical properties that make them attractive candidates for photodynamic therapy (PDT). Tissue distributions were studied in normal and in tumor-bearing rats as a function of time following intravenous injection of isoBOSINC as a suspension in 10% Tween 80 in saline. The dose studied was 0.25 mg/kg of body weight. The compound isoBOSINC was isolated from several tissues and organs, as well as tumors and peritumoral muscles and skin, and quantitated by a high-performance liquid chromatographic technique. The tumor model, an N-(4-[5-nitro-2-furyl]-2-thiazolyl)formamide (FANFT)-induced urothelial cell carcinoma, was transplanted into the hind legs of Fischer 344 rats. The dye was retained in tumors at higher concentrations than in all tissues and organs examined, except for spleen and liver. The highest concentration ratio of dye in tumor versus peritumoral muscle (24.5) occurred 9 h after injection. Serum clearance of isoBOSINC showed similar kinetic behavior for both groups of rats, with a t 1/2 of elimination of approximately 10 h. At 7 and 14 days postinjection, the levels of dye found in testes were generally higher than in most other tissues, except spleen and liver. Concentrations of isoBOSINC were either very low or not detectable in rat brain. Trace amounts of the dye were excreted in the urine, and by day 14 approximately 17% of the dose was accounted for in the feces. The significant levels of the drug in tumors, as well as the excellent ratios of tumor-to-muscle concentration observed, have promising implications for PDT of tumors.

Animals↗

PubMed1989

Tissue distribution and characterization of prorenin-converting enzyme in mouse.

Renin is produced from an inactive precursor, prorenin, through endoproteolytic cleavage at paired basic amino-acid residues. Using (35S)methionine-labeled prorenin, that was synthesized with Xenopus oocyte expression system, as a substrate, we have determined the tissue distribution and the nature of prorenin-converting activity in mouse. The highest activity was found in the submandibular gland of male ICR mouse. The activity of the enzyme seemed to be parallel to that of renin. This enzyme activity, with an optimal pH 8.0-8.5, was inhibited by leupeptin, antipain and benzamidine.

Animals↗

PubMed1982

Rat major histocompatibility RT1.C antigens of restricted tissue distribution consist of two polypeptide chains with molecular weights of about 42 000 and 12 500.

The RT1.C region has recently been defined genetically as a third region of the rat major histocompatibility system, RT1, and has been shown to code for cell-surface antigens with restricted tissue distribution (present on lymphocytes and absent from red blood cells and liver) and for target antigens of unrestricted cytotoxic T lymphocytes. Immunoprecipitation with C-antigen-specific alloantisera and SDS-PAGE analysis, reveal that C-region products are glycoproteins composed of molecules of 40 500-43 000 and 12 500 molecular weight, respectively. Thus, the RT1.B region, which codes for class II molecules, is flanked by RT1 regions which determine class I molecules (as defined biochemically), which are either expressed ubiquitously (RT1.A antigens) or in a restricted manner (RT1.C products). The homology to H-2Qa antigens is discussed.

Animals↗