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T Shigenaga

Publications and source records attributed to T Shigenaga.

At least 19 recordsLinked to original sources
PubMed2001

beta-Phenylethylamine modulates acetylcholine release in the rat striatum: involvement of a dopamine D(2) receptor mechanism.

We examined the effects of beta-phenylethylamine on striatal acetylcholine release in freely moving rats using in vivo microdialysis. beta-Phenylethylamine at 12.5 mg/kg, i.p. did not affect acetylcholine release in the striatum, whereas 25 and 50 mg/kg, i.p. immediately induced an increase in acetylcholine release in the striatum at 15-45 min. This increase following intraperitoneal administration of beta-phenylethylamine (25 mg/kg) was not affected by locally applied SCH-23390 (R(+)-7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine, 10 microM), a dopamine D(1) receptor antagonist, nor by raclopride (10 microM), a dopamine D(2) receptor antagonist. The increased release of acetylcholine induced by beta-phenylethylamine was suppressed by local infusion of tetrodotoxin (1 microM). In contrast, the extracellular acetylcholine level in the striatum was significantly decreased by local application of beta-phenylethylamine (10 and 100 microM) in the striatum via a microdialysis probe. The decrease was completely blocked by local co-application of raclopride (10 microM). The beta-phenylethylamine-induced decrease in striatal acetylcholine release was not affected by co-perfusion with SCH-23390 (10 microM). These results indicate that systemic administration of beta-phenylethylamine increases acetylcholine release, whereas locally applied beta-phenylethylamine decreases striatal acetylcholine release in freely moving rats. Furthermore, the dopaminergic system, through the dopamine D(2) receptor, is involved in the locally applied beta-phenylethylamine-induced decrease in acetylcholine in the striatum.

Acetylcholine↗
PubMed2001

Immune responses in tuberculosis: antibodies and CD4-CD8 lymphocytes with vascular adhesion molecules and cytokines (chemokines) cause a rapid antigen-specific cell infiltration at sites of bacillus Calmette-Guérin reinfection.

Rabbit primary dermal bacillus Calmette-Guérin (BCG) lesions were compared with reinfection BCG lesions in order to gain insight into how immune responses protect against clinical tuberculosis. As early as 3 hr, a marked infiltration of macrophages and lymphocytes occurred in the reinfection group, while very little cell infiltration occurred in the primary group. It seems that only an antigen-antibody reaction could produce such an immediate pronounced antigen-specific chemotactic effect, because very few lymphocytes are normally present in the skin. Therefore, antibodies hasten the accumulation of an expanded antigen-specific T-lymphocyte population (memory cells) at sites of bacillary lodgement. By 1-2 days, the primary and reinfection BCG lesions differed 400- to 500-fold in size. By 4-5 days, the size of the reinfection lesions had declined, while the size of the primary lesions had increased, so that, grossly, both types of lesion were similar. At 8 days in reinfection lesions and at 12 days in primary lesions, small secondary peaks in size occurred, which were probably caused by cell-mediated immune responses. In rabbits with primary BCG lesions, skin tests with Old Tuberculin were positive at 9 days, accompanied by a rise in the levels of antibodies to the secreted antigen, phosphate-specific transport protein 1, but the levels of antibodies to the constitutive antigens, purified protein derivative and heat-shock protein 65, did not increase appreciably until some time after 23 days. In tissue sections of reinfection BCG lesions, the percentage of mononuclear cells labelled, by in situ hybridization techniques, for the mRNA of monocyte chemoattractant protein 1 (MCP-1), a chemokine, peaked at 3 hr and then was down-regulated, whereas in primary lesions, this percentage was down-regulated only after 2 days. [The percentage in the tissue sections for the mRNAs of interleukins 1beta and 8, as well as the proteins of MCP-1 and tumor necrosis factor alpha (TNF-alpha), followed a somewhat similar time-course to that of MCP-1 mRNA.] A high percentage of mononuclear cells containing the MCP-1 mRNA 'factory' would favour enlargement of the lesions and a low percentage would favour their regression. At 5 days, the percentage of CD4 and CD8 lymphocytes, stained by immunohistochemical techniques, and the amount of microvasculature stained similarly for vascular cell adhesion molecule 1 were higher in the reinfection group, indicating that prior immunization caused a more rapid (antigen-dependent) up-regulation of these factors. Tuberculin reactions resembled early reinfection BCG lesions in almost every factor evaluated herein. In brief, the production of chemokines began soon after BCG reinfection, peaked within a few hours and was markedly down-regulated by 24 hr, a time at which the lesions of reinfection were of maximal size. Therefore, the amount of cell infiltration was tightly controlled, probably by the variety of mechanisms listed herein.

Animals↗
PubMed2001

[A case of chronic hypersensitivity pneumonitis due to wild pigeons].

A 61-year-old woman was admitted to the Oita Medical University Hospital because of a nonproductive cough and exertional dyspnea. Interstitial changes had been seen on her chest radiograph 5 years previously, but no respiratory symptoms were identified at that time. On admission, chest radiography revealed linear and ground-glass opacities in the middle and lower lung fields. Computed tomography provided evidence of bronchiectasis and micro-honeycombing of the lungs, while lymphocyte and neutrophil counts in the bronchoalveolar lavage fluid were increased. Transbronchial lung biopsy demonstrated alveolitis and Masson's bodies. The patient was not a pigeon breeder, but she could have been exposed to pigeons at her workplace. Indeed, she had specific antibodies against pigeon serum and droppings, and her peripheral lymphocytes showed proliferation in response to pigeon serum. A positive provocation test involving inhalation of pigeon serum confirmed that she had chronic hypersensitivity pneumonitis caused by allergy to pigeons. This is a rare case of chronic hypersensitivity pneumonitis associated with wild pigeons, that progressed to pulmonary fibrosis. Antigen provocation testing proved to be of great value.

Alveolitis, Extrinsic Allergic↗
PubMed2000

[Misoprostol-induced pneumonitis].

A 76-year-old woman presented with non-productive cough and progressive dyspnea, and was admitted to Oita Medical University Hospital. Arterial blood gas values obtained on admission indicated severe hypoxemia. Chest roentgenograms and computed tomography disclosed diffuse interstitial infiltrates in both lungs. Transbronchial lung biopsy specimens demonstrated thickened alveolar walls with lymphocyte infiltration and swollen type II pneumocyte proliferation. Eosinophils were observed mainly around bronchioles. For approximately 6 months prior to hospitalization, the patient had been given misoprostol, sodium aurothiomalate, prednisolone, and loxoprofen sodium for the treatment of rheumatoid arthritis. Based on the clinical history and findings, drug-induced interstitial pneumonia was suspected. All medications were discontinued, and the patient was then placed on corticosteroids. After treatment, arterial blood gas values improved and the findings on chest roentgenograms cleared up. Positive lymphocyte stimulation tests and positive dermal reaction patch tests implicated misoprostol as an etiologic factor in the patient's interstitial pneumonia. High serum levels of KL-6 and cytokeratin subunit 19 fragment had been detected on admission. These values returned to normal after the interstitial infiltrates had disappeared. To our knowledge, this is the first reported case of misoprostol-induced interstitial pneumonia.

Aged↗
PubMed2000

Effects of microiontophoretically-applied opioid peptides on Purkinje cells in the cat cerebellum.

AIM: The purpose of the present study was to examine the effects of microiontophoretically-applied opioid peptides on Purkinje cell of the cerebellum. METHODS: The effects of microiontophoretically-applied morphine, leucine-enkephalin (Leu-Enk), methionine-enkephalin (Met-Enk), and dynorphin 1-13 (Dyn) on the spontaneous discharge of Purkinje cells in the cerebellum of the anesthetized cat were examined. RESULTS: Microiontophoretic applications of Leu-Enk and morphine produced inhibitory and excitatory responses, respectively in Purkinje cells. Application of both morphine and Leu-Enk induced dose-dependent responses. The excitatory responses were antagonized by naloxone, whereas the inhibitory responses were not. Bicuculline, a GABA-A antagonist, completely abolished both the Leu-Enk- and morphine-induced-inhibitory responses. Iontophoretic application of Met-Enk and dyn produced inhibitory responses only. Met-enk- and dyn-induced inhibition was antagonized by naloxone. CONCLUSION: In Purkinje cell activity, microiontophoretically applied Leu-Enk- and morphine-induced excitation is connected with opiate receptors, whereas inhibition is related to the GABA receptor. However, Met-Enk and dyn produced only inhibitory effects via an opiate receptor in the cerebellum of cats.

Action Potentials↗
PubMed1998

The effect of methamphetamine on the release of acetylcholine in the rat striatum.

We examined the effect of methamphetamine on the release of acetylcholine in the striatum of freely moving rats, using an in vivo microdialysis method. The basal level of acetylcholine was 3.67+/-0.47 pmol/30 microl per 15 min in the presence of neostigmine (10 microM). Tetrodotoxin (1 microM), a selective blocker of voltage-dependent Na+ channels, markedly inhibited the release of acetylcholine in the striatal perfusates. Apomorphine (1.0 mg/kg, i.p.), a dopamine receptor agonist, also significantly attenuated acetylcholine release. Methamphetamine (0.1 and 0.5 mg/kg, i.p.) did not immediately affect acetylcholine release in the striatum, but a dose of 1.0 mg/kg (i.p.) induced an increase of acetylcholine release in the striatum at 15-60 min. Striatal infusion of methamphetamine (5 and 10 microM) did not influence acetylcholine release. The increase following intraperitoneal administration of methamphetamine was slightly diminished by haloperidol (0.5 mg/kg). After microinjection of the neurotoxin, 6-hydroxydopamine (6 microg/3 microl), in the substantia nigra 7 days before, the increase of acetylcholine induced by the administration of methamphetamine (1.0 mg/kg) was slightly attenuated, whereas the administration of reserpine (2 mg/kg, i.p.) 24 h before, combined with alpha-methyl-p-tyrosine (300 mg/kg, i.p.) 2.5 h before, completely blocked the increase in release of acetylcholine. These findings suggest that methamphetamine exerts an excitatory influence on striatal acetylcholine release in freely moving rats, and that this excitatory effect involves the dopaminergic system and the catecholaminergic system.

Acetylcholine↗
PubMed1998

Pulmonary bovine-type tuberculosis in rabbits: bacillary virulence, inhaled dose effects, tuberculin sensitivity, and Mycobacterium vaccae immunotherapy.

This report elucidates four aspects of the immunology of pulmonary tuberculosis produced in rabbits: (i) the virulence of bovine-type tubercle bacilli, strain Ravenel S, (ii) systemic factors influencing the generation of visible primary pulmonary tubercles, (iii) differences in tuberculin sensitivity of rabbits and humans, and (iv) the effect of Mycobacterium vaccae immunotherapy on cavitary tuberculosis. Laboratory strain Ravenel S (ATCC 35720) was not fully virulent. Fully virulent strains produce one visible primary pulmonary tubercle for each three bacillary units inhaled. Strain ATCC 35720 produced one such tubercle for each 18 to 107 bacillary units inhaled, indicating that its virulence was reduced by 6- to 36-fold. When a low dose of this Ravenel S strain was inhaled, the host resistance (measured by the number of inhaled bacilli needed to generate one visible primary pulmonary tubercle) was increased at least 3.5-fold compared to the host resistance when a high dose was inhaled. Rabbits and humans differ in the degree and in the maintenance of their dermal sensitivities to tuberculin. Compared to rabbits, humans are 100 times more sensitive to tuberculin. Also, at 33 weeks rabbits with well-controlled cavitary tuberculosis usually showed a decrease in their tuberculin reactions of about 50% from peak values, whereas humans with such well-controlled tuberculosis are thought to maintain strong reactions for many years. These species differences may be due to desensitization to group II mycobacterial antigens in the rabbits because they have a different diet and a different type of digestive tract. M. vaccae immunotherapy of rabbits with cavitary tuberculosis produced no statistically significant effects. Experiments with many more rabbits would be required to prove whether or not such immunotherapy is beneficial.

Animals↗
PubMed1997

In vivo voltammetric studies of the effects of intrathecal morphine on noxious heat stimuli-induced serotonin release in the nucleus raphe magnus of anesthetized rats.

The effects of cutaneous noxious heat stimuli and intrathecal administration of morphine on the oxidation current of 5-hydroxytryptamine (serotonin: 5-HT) in the nucleus raphe magnus (NRM) were examined in anesthetized rats. An oxidation current of 5-HT was seen at 320-340 mV using differential normal pulse voltammetry with nafion-coated carbon fiber electrodes. The signal was decreased by 28.5 +/- 5.7 and by 12.7 +/- 4.1% after cutaneous noxious heat stimuli of 52 and 45 degrees C, respectively. These decreases lasted for 5-10 min. Non-noxious stimuli (37 degrees C) did not affect the 5-HT signal. Intrathecal administration of morphine (2.5, 5.0, 10.0 and 15.0 microg) in the absence of cutaneous stimulation did not change the signal significantly. However, low doses of morphine (2.5 or 5.0 microg, i.t.) potentiated the decrease in the 5-HT signal induced by noxious stimuli, and high doses (10.0 or 15.0 microg, i.t.) attenuated it. Both effects of morphine at low and high doses were antagonized by naloxone (0.5 mg/kg, i.p.). These results indicate that the intrathecal administration of morphine affects the cutaneous noxious heat stimulus-induced decrease of serotonin release in the NRM.

Animals↗
PubMed1997

Elevated soluble intercellular adhesion molecules-1 in inflammatory myopathy.

INTRODUCTION: We evaluated the serum level of soluble intercellular adhesion molecule-1 (sICAM-1) in patients with polymyositis (PM) and dermatomyositis (DM) and investigated the correlation between the serum level of sICAM-1 and clinical findings. MATERIAL AND METHODS: We measured the serum level of sICAM-1 using an enzyme-linked immunosorbent assay in 19 untreated patients with inflammatory myopathy (14 patients with PM and 5 patients with DM), 20 patients with other neuromuscular disorders in which immunological mechanisms are unlikely to be involved, and 14 normal healthy controls. RESULTS: The serum level of sICAM-1 was significantly higher in patients with PM/DM compared with patients with other neurological disorders and control subjects. The sICAM-1 level was, however, not correlated with the clinical characteristic including disease severity, the duration of illness, and the serum level of CK. CONCLUSION: These findings suggest that sICAM-1 is involved in the inflammatory process of PM and DM.

Adult↗
PubMed1997

[Meigs' syndrome associated with adenocarcinoma of the left fallopian tube].

A 52-year-old woman was admitted to the hospital with dyspnea on exertion and a feeling of abdominal fullness. Chest radiographs revealed a moderate bilateral pleural effusion. Examination of the effusion was in conclusive. Thoracoscopy and thoracic computed tomography (CT) failed to provide evidence pertaining to the etiology of the recurrent effusion. Elevation of serum CA-125 levels suggested the presence of an intrapelvic tumor, which was substantiated by pelvic CT. Laparotomy revealed a small amount of ascites. The resected specimen revealed a tumor of the left fallopian tube, which was histologically to be poorly differentiated adenocarcinoma. The pleural effusion disappeared after removal of the tumor and Meigs' syndrome was subsequently diagnosed. Primary fallopian tube adenocarcinoma is a rare cause of Meigs' syndrome.

Adenocarcinoma↗
PubMed1996

Tachycitin, a small granular component in horseshoe crab hemocytes, is an antimicrobial protein with chitin-binding activity.

Small granules of horseshoe crab hemocytes contain two known major antimicrobial substances, tachyplesin and big defensin (S5), and at least five protein components (S1 to S6), with unknown functions. In the present study, we examined the biological properties and primary structure of a small granular component S2, named tachycitin. This component was purified from the acid extract of hemocyte debris by two steps of chromatography. The purified tachycitin was a single chain protein with an apparent M(r) = 8,500 on Tricine-SDS-polyacrylamide gel electrophoresis. Ultracentrifugation analysis revealed tachycitin to be present in monomer form in solution. Tachycitin inhibited the growth of both Gram-negative and -positive bacteria, and fungi, with a bacterial agglutinating property. Moreover, tachycitin and big defensin acted synergistically in antimicrobial activities. The amino acid sequence and intrachain disulfide bonds of tachycitin were determined by amino acid and sequence analyses of peptides produced by enzymatic cleavages. The mature tachycitin consisted of 73 amino acid residues containing five disulfide bonds with no N-linked sugar. A cDNA coding for tachycitin was isolated from a hemocyte cDNA library. The open reading frame coded for an NH2-terminal signal sequence followed by the mature peptide and an extension sequence of -Gly-Arg-Lys at the COOH-terminus, which is a putative amidating signal. The COOH-terminal threonine amide released after digestion of tachycitin with lysylendopeptidase was identified. The NH2-terminal 28 residues of tachycitin shows sequence homology to a part of chitin-binding regions found in antifungal chitin-binding peptides, chitin-binding lectins, and chitinases, all of which have been isolated from plants. Tachycitin showed a specific binding to chitin but did not bind with the polysaccharides cellulose, mannan, xylan, and laminarin. Tachycitin may represent a new class of chitin-binding protein family in animals.

Amino Acid Sequence↗
PubMed1995

A novel big defensin identified in horseshoe crab hemocytes: isolation, amino acid sequence, and antibacterial activity.

Hemocytes of the horseshoe crab (limulus) contain a family of arthropodous peptide antibiotics, termed the tachyplesin family, and antibacterial protein, called anti-LPS factor, of which the former is located in the small (S) granules and the latter in the large (L) granules of the hemocytes. In our ongoing studies on granular components, we have identified here a novel defensin-like substance present in both L- and S-granules. This substance strongly inhibits the growth of Gram-negative and -positive bacteria, and fungi, such as Candida albicans. The isolated substance, tentatively termed "big defensin," consists of 79 amino acid residues, of which the COOH-terminal 37 residues have a sequence similar to those of mammalian neutrophil-derived defensins, especially rat defensin. Characterization of the disulfide motif in big defensin indicated that the disulfide array is identical to that of beta-defensins from bovine neutrophils. One clear structural difference is that the limulus hemocyte-derived big defensin has an extension of the NH2-terminal hydrophobic sequence with 35 amino acid residues followed by the COOH-terminal cationic defensin portion. This amphipathic nature of big defensin seems likely to be associated with its potent antibacterial activity. Furthermore, antibacterial activities of the NH2-terminal hydrophobic region and the COOH-terminal defensin portion separated by tryptic digestion are significantly different: the former displays a more potent activity against Gram-positive bacteria, whereas the latter is more potent against Gram-negative bacteria. Big defensin, therefore, may prove to represent a new class of defensin family possessing two functional domains with different antimicrobial activities.

Amino Acid Sequence↗
PubMed1995

A case of acute eosinophilic pneumonia caused by inhalation of Trichosporon terrestre.

We present the diagnostically challenging case of an 18-yr-old Japanese woman who presented with fever, nonproductive cough, and acute respiratory distress. Her chest radiograph showed diffuse interstitial infiltrates and bilateral pleural effusions. Eosinophilic pneumonia was diagnosed by bronchoalveolar lavage and transbronchial lung biopsy. She was treated with minocycline, and was discharged in 2 wk. However, within 3 h of returning home, she experienced a recurrence. She showed positive immediate, Arthus, and delayed-type skin reactions and positive lymphocyte stimulation test to an antigen derived from Trichosporon terrestre, which was isolated from dust in her home. In addition, a bronchoprovocation test with the same antigen caused a nonproductive cough with fever, hypoxemia, and peripheral eosinophilia. We concluded that T. terrestre was the causal agent of the acute eosinophilic pneumonia.

Acute Disease↗
PubMed1994

Role of hemocyte-derived granular components in invertebrate defense.

Figure 2 illustrates an outline of the cellular and humoral defense systems in limulus. On the basis of the knowledge described above, it is suggested that granular components present in L and S granules in the hemocytes play a decisive role in the biological defense for this animal. The isolated L granules contain at least three clotting factors plus coagulogen as the major component. The known anti-LPS factor and a number of additional unknown protein components are also present in the L granules. On the other hand, the isolated S granules contain antimicrobial tachyplesins as the major component, in addition to six unidentified proteins. We speculate that the L-granule-derived protein components, which probably contain all the factors essential for the Limulus clotting system participate, in immobilizing invading microbes, and that the S-granule-derived tachyplesins contribute to a self-defense system against invaders. Although we have not mentioned hemolymph plasma components, there are many humoral factors, such as proteinase inhibitors, alpha 2-macroglobulin, various lectins, C-reactive protein, and polyphemin, all of which are important for antimicrobial defense. Furthermore, Liu and colleagues have reported several endotoxin-binding proteins and a cell-adhesion protein found in the Limulus hemocytes. Although the exact functions of these substances are unknown, they may act in concert with other components to provide biological defense for the animal. Nevertheless, compared to our knowledge of mammalian blood cells, much less remains to be learned of biological/physiological events in horseshoe crab hemocytes.

Amino Acid Sequence↗
PubMed1994

Structure-function relationships of tachyplesins and their analogues.

Haemocytes of the horseshoe crab (Limulus) contain a new family of arthropodous peptide antibiotics, termed the tachyplesin family. These cationic peptides are composed of 17-18 amino acid residues with a C-terminal arginine alpha-amide. Tachyplesin I takes on a fairly rigid conformation constrained by two disulphide bridges and adopts a conformation consisting of an antiparallel beta-sheet connected by a beta-turn. Isopeptides of tachyplesin I with amino acid replacements, tachyplesins II and III, and polyphemusins I and II have also been found in the haemocytes of the South-East Asian species and Limulus polyphemus. These peptides are present in abundance in the small granules of the haemocytes and inhibit strongly the growth of not only Gram-negative and Gram-positive bacteria but also fungi such as Candida albicans. Tachyplesin exists in the prepro form consisting of 77 residues; this precursor is probably processed by intracellular proteases and an amidation enzyme before incorporation into the small granules of the haemocytes. We examined the mode of action of tachyplesin I on biomembranes, comparing it with that of gramicidin S. Tachyplesin caused an efflux of K+ from Staphylococcus aureus and Escherichia coli cells similar to that caused by gramicidin S. Another antimicrobial substance, anti-LPS factor, has been isolated from haemocytes.

Amino Acid Sequence↗
PubMed1993

Separation of large and small granules from horseshoe crab (Tachypleus tridentatus) hemocytes and characterization of their components.

We designed a method for separating two types of granules, a smaller (S) but dense and a larger (L) but less dense granule from hemocytes of the horseshoe crab (Tachypleus tridentatus), using continuous sucrose density gradient centrifugation. The isolated L-granules contained at least three clotting factors plus a clottable protein, coagulogen, as the major component. The known anti-lipopolysaccharide factor and 7 additional unknown protein components were also present in the L-granules. Two known natural substrates, Pro-rich protein and 8.6 kDa protein, for limulus transglutaminase [Tokunaga, F., Yamada, M., Miyata, T., Ding, Y.-L., Hiranaga-Kawabata, M., Muta, T., Iwanaga, S., Ichinose, A., & Davie, E.W. (1993) J. Biol. Chem. 268, 252-261] were present in the L-granules. On the other hand, the isolated S-granules contained antimicrobial tachyplesins I and II (17 amino acids in length) as the major component, in addition to 6 unidentified proteins with molecular masses of less than 30 kDa. The structural analyses of tachyplesin analogs indicated that all these peptides of mature form are stored in the S-granules, together with a processing intermediate containing the COOH-terminal Gly-Lys sequence. We also found an Arg-rich protein of 22 kDa and a Leu-rich protein of 30 kDa in S-granules. Based on these observations, we speculate that protein components in L-granules, which probably contain all the factors essential for the limulus clotting system, participate in immobilization of invading microbes and that factors in the S-granules containing tachyplesins contribute to a self-defense system against invaders.

Amino Acid Sequence↗
PubMed1990

Antimicrobial tachyplesin peptide precursor. cDNA cloning and cellular localization in the horseshoe crab (Tachypleus tridentatus).

The hemocytes of the horseshoe crab have been found to contain a new family of Arthropodous antibiotics, termed the "tachyplesin family." These peptides are composed of 17-18 amino acid residues with a carboxyl-terminal arginine alpha-amide. We report here the entire cDNA sequence coding for the tachyplesin precursors and their distribution in various tissues of the horseshoe crab. Sequence analysis of the cloned cDNAs revealed that the tachyplesin precursors consist of 77 amino acids with 23 residues in a presegment, and that there are two types of mRNAs corresponding to the isopeptides tachyplesins I and II. Both precursors contain a putative signal peptide, a processing peptide sequence and a carboxyl-terminal amidation signal "Gly-Lys-Arg" connected to the mature tachyplesin peptide. Moreover, an unusual acidic amino acid cluster, Asp-Glu-Asp-Glu-Asp-Asp-Asp-Glu-Glu-COOH, is present in the carboxyl-terminal portions of both precursors. These results suggest that the two types of tachyplesin precursors are first synthesized as preproproteins and are then incorporated into the intracellular organelle, accompanied by various processing events. Northern blot analysis on a total RNA from various tissues of the horseshoe crab revealed that the tachyplesin precursors are expressed mainly in hemocytes and cardiac and brain tissues. Tachyplesin was immunohistochemically localized in the smaller dense granules rather than the typical large granules present in abundance in the hemocytes.

Amino Acid Sequence↗