Search PubMed⌕ Search

Biomedical subjects

C Yanaihara

Publications and source records attributed to C Yanaihara.

At least 73 records · Page 4Linked to original sources
PubMed1985

[Met-enkephalin-Arg-Gly-Leu-like immunoreactivity-containing nerve elements in the guinea-pig intestine. An immunohistochemical study using whole mount preparations].

The localization and distribution of Met-enkephalin-Arg-Gly-Leu (Met-Enk-Arg-Gly-Leu)-like immunoreactivity in whole mount preparations of different layers of guinea-pig gut (duodenum, jejunum, ileum and proximal colon) were studied by Sternberger's indirect immunocytochemistry. Anti-Met-Enk-Arg-Gly-Leu serum used as the primary antiserum was raised in a rabbit against synthetic Met-Enk-Arg-Gly-Leu coupled to ascaris protein by the glutaraldehyde method. The results obtained were summarized as follows: In the intestinal wall of the guinea-pig, Met-Enk-Arg-Gly-Leu-like immunoreactivity was localized only in nerve elements of the enteric nervous system. In the myenteric plexus, many perikarya showed Met-Enk-Arg-Gly-Leu-like immunoreactivity. Immuno-positive nerve fibers showing varicose appearance were demonstrated not only in the myenteric plexus but also in the longitudinal muscle layer, in the circular muscle layer, in the deep muscular plexus, in the submucous plexus and in the muscularis mucosae. No immuno-positive perikarya were found in the submucous plexus. Met-Enk-Arg-Gly-Leu-like immunoreactivity was not shown in the perivascular plexus and in the mucosa. Compared to those of the duodenum, jejunum or ileum, immuno-positive perikarya in the myenteric plexus of the proximal colon were apparently few in number. The density of a network in the deep muscular plexus formed by immunoreactive fibers was looser in the proximal colon than that in the duodenum, jejunum or ileum. Since Met-Enk-Arg-Gly-Leu-like immunoreactivity-containing nerve elements were densely distributed in the muscular layers of the intestinal wall, it is possible for this nervous system to regulate the contractility of the smooth muscles of the gut.

Animals↗
PubMed1985

Rat pancreas contains the proglucagon(64-69) fragment and arginine stimulates its release.

Rat proglucagon(64-69) corresponding to the C-terminal hexapeptide of putative rat glicentin sequence in the precursor was synthesized. A glicentin C-terminal hexapeptide specific radioimmunoassay, using the synthetic hexapeptide as standard, demonstrated the presence in rat pancreas of a peptide identified with the synthetic rat proglucagon(64-69): H-Asn-Arg-Asn-Asn-Ile-Ala-OH. The hexapeptide was released concomitantly with glucagon by arginine stimulation from the isolated perfused rat pancreas. The results indicate that the pancreas co-stores and possibly co-releases the hexapeptide with glucagon as one of the processing products of proglucagon.

Amino Acid Sequence↗
PubMed1985

Immunoreactive helodermin-like peptides in rat: a new class of mammalian neuropeptides related to secretin and VIP.

Helodermin is a peptide from the venom of the lizard Heloderma suspectum (Gila Monster) showing a high degree of sequence similarity with VIP, PHI and secretin in its N-terminal moiety. The present data support the presence of peptide(s) closely related to helodermin in the brain, gut and salivary glands of rat. In our radioimmunoassays, we routinely used one of the three specific antisera obtained from rabbits that were immunized against lizard helodermin coupled to bovine serum albumin with carbodiimide. Heat- and acid-stable immunoreactive helodermin-like material was more abundant in striatum, hippocampus and anterior pituitary than in cerebral cortex and hypothalamus. High levels of helodermin-like material were also present in salivary glands, duodenum and jejunum. When submitted to gel permeation chromatography on a TSK-G 2000 SW column, the apparent molecular radius of most of the immunoreactive material ranged from 6 to 12 KDa.

Animals↗
PubMed1985

Methionine-enkephalin-Arg6-Gly7-Leu8-immunoreactive nerve fibers and cell bodies in lumbar paravertebral ganglia and the celiac-superior mesenteric ganglion complex of the rat: an immunohistochemical study.

Lumbar paravertebral ganglia and prevertebral ganglia of the rat were immunohistochemically examined using an antiserum against Methionine-enkephalin-Arg6-Gly7-Leu8 (Met-Enk-Arg-Gly-Leu). Colchicine (5 mg/kg body wt., i.p. injection) was employed as an axonal transport blocker to intensify the immunoreactivity in the nerve cell bodies. In the lumbar paravertebral ganglia of the colchicine-treated rats, about 55% of nerve cell bodies showed a positive immunoreactivity. In the celiac-superior mesenteric ganglion complex, a dense network of positively immunostained nerve fiber varicosities surrounded immunonegative nerve cell bodies. The Met-Enk-Arg-Gly-Leu-like immunoreactivity demonstrated in this study suggests the occurrence of preproenkephalin A and related opioid peptides.

Animals↗
PubMed1985

[Met-enkephalin-Arg-Gly-Leu-like immunoreactivity-containing nerve fibers and cell bodies in the abdominal sympathetic ganglia of the rat--an immunohistochemical study].

The occurrence and localization of Met-enkephalin-Arg-Gly-Leu (Met-Enk-Arg-Gly-Leu)-like immunoreactivity in the lumbar paravertebral ganglion and the superior mesenteric ganglion in the rat were investigated by immunocytochemistry. Colchicine was employed as an axonal flow blocker to accumulate Met-Enk-Arg-Gly-Leu in the nerve cell bodies. The Met-Enk-Arg-Gly-Leu serum (R 0171) was produced by immunizing a mixed breed female rabbit with synthetic Met-Enk-Arg-Gly-Leu conjugated to ascaris protein by the glutaraldehyde method. Sections, 7 micron in thickness, of Bouin-fixed and paraffin-embedded tissues were immunostained by the peroxidase-antiperoxidase (PAP) method. Results obtained were summarized as follows: Colchicine-untreated rats possessed no strongly-immunoreactive nerve cell bodies for Met-Enk-Arg-Gly-Leu in the lumbar paravertebral ganglion, though a few of them were weakly immunopositive. Met-Enk-Arg-Gly-Leu-like immunoreactivity showing nerve fibers were occasionally seen in nerve fiber bundles of the lumbar paravertebral ganglion. In the superior mesenteric ganglion, a dense network of positively immunostained nerve fibers with a beaded appearance were seen around nerve cell bodies which were immunonegative for Met-Enk-Arg-Gly-Leu. In colchicine-treated rats, 55 percent of nerve cell bodies of the lumbar paravertebral ganglion showed various degrees of positive immunoreactivities for Met-Enk-Arg-Gly-Leu. Many strongly immunostained nerve terminals were seen in the lumbar paravertebral ganglion of colchicine-treated rats. In the superior mesenteric ganglion, the immunoreactivity for Met-Enk-Arg-Gly-Leu in the beaded nerve fibers around nerve cell bodies was intensified by the colchicine treatment, whereas the nerve cell bodies themselves remained immunonegative for Met-Enk-Arg-Gly-Leu.

Animals↗
PubMed1985

Vagal regulation of GRP, gastric somatostatin, and gastrin secretion in vitro.

The effect of electrical stimulation of the vagus nerves on the release of immunoreactive gastrin-releasing peptide (GRP), gastrin, and somatostatin was investigated using the isolated perfused rat stomach. Electrical stimulation (10 Hz, 1 ms duration, 10 V) of the peripheral end of the subdiaphragmatic vagal trunks produced a significant increase in both GRP and gastrin but a decrease in somatostatin. The infusion of atropine sulfate at a concentration of 10(-5) M augmented GRP release and reversed the decrease in somatostatin release in response to vagal stimulation to an increase above basal levels. However, the gastrin response to vagal stimulation was not affected by atropine. The infusion of hexamethonium bromide at a concentration of 10(-4) M significantly suppressed GRP release but did not affect gastrin secretion in response to vagal stimulation. On the other hand, the somatostatin response to vagal stimulation was completely abolished by hexamethonium. These findings lead us to conclude that the intramural GRP neurons might play an important role in the regulation of gastrin as well as somatostatin secretion and that somatostatin secretion may be controlled not only by a cholinergic inhibitory neuron but also by a noncholinergic, e.g., peptidergic stimulatory neuron, both of which may be regulated through preganglionic vagal fibers via nicotinic receptors. In addition, because the infusion of 10(-7) M GRP suppressed the somatostatin secretion, we suggest that either GRP should be excluded from the list of candidates for the noncholinergic stimulatory neurotransmitter for somatostatin secretion or that there are different mechanisms of action for endogenous and exogenous GRP.

Animals↗
PubMed1984

Primary structure of helodermin, a VIP-secretin-like peptide isolated from Gila monster venom.

The complete amino acid sequence of helodermin isolated from the venom of Gila monster was elucidated. The peptide was shown to be a basic pentatriacontapeptide amide: His-Ser-Asp-Ala-Ile-Phe-Thr-Gln-Gln-Tyr-Ser-Lys-Leu-Leu-Ala-Lys-Leu-Ala- Leu-Gln-Lys- Tyr-Leu-Ala-Ser-Ile-Leu-Gly-Ser-Arg-Thr-Ser-Pro-Pro-Pro-NH2. A high degree of sequence similarities to secretin/VIP/PHI/(PHM)/GRF from mammal and bird was observed over the entire N-terminal 1-27 sequence. In particular, the amino acid residues in positions 3, 6 and 7 were found to be common to 9 peptides of the family. Another interesting feature of the structure of helodermin was its C-terminal -Pro-Pro-Pro-NH2 sequence. Isolation of helodermin was the first demonstration of the existence of a secretin/VIP-related peptide in an animal that is neither mammal nor bird.

Amino Acid Sequence↗
PubMed1984

Human leumorphin is a potent, kappa opioid receptor agonist.

The opioid activity and opioid receptor type specificity of synthetic human leumorphin were studied in vitro. Human leumorphin inhibited the contraction of the myenteric plexus-longitudinal muscle preparation of the guinea pig ileum and was similar in opioid potency to porcine leumorphin. This action of human leumorphin was antagonized less effectively by naloxone than by the opiate antagonist Mr 2266. Human leumorphin also inhibited the contraction of the rabbit vas deferens which has only the kappa-type opioid receptor. It is concluded that human leumorphin has potent opioid activity and acts as an agonist at the kappa-type opioid receptor, like porcine leumorphin and other peptides derived from preproenkephalin B.

Animals↗
PubMed1984

[Met-enkephalin-Arg-Gly-Leu-like immunoreactivity-containing nerve elements in the canine pancreas--an immunohistochemical study].

The occurrence and localization of Met-enkephalin-Arg-Gly-Leu (Met-Enk-Arg-Gly-Leu)-like immunoreactivity in the canine pancreas were studied by immunocytochemistry. For light microscopy, Bouin fixed and paraffin embedded sections were immunostained by the PAP method. For electron microscopy, ultrathin sections of 4% paraformaldehyde-fixed and Araldite embedded materials were immunostained by a protein A-colloidal gold method. The results obtained were as follows: In light microscopy, Met-Enk-Arg-Gly-Leu-like immunoreactivity was localized in nerve fibers of autonomic ganglion, in beaded nerve terminals around blood vessels of the exocrine parenchyma and pancreatic islet, in eighty-five out of one hundred and seventy-four ganglion cell somas of intra- and interlobular ganglia, and in ganglion cell somas and nerve fibers of neuro-insular complexes. In electron microscopy, colloidal gold particles representing Met-Enk-Arg-Gly-Leu-like immunoreactivity were concentrated on secretory type granules of the ganglion cell somas and on large cored synaptic vesicles of the nerve terminals around blood capillaries. All the positive immunoreactions disappeared with preincubation of the anti-Met-Enk-Arg-Gly-Leu serum (dilution, 1:4,000) with Met-Enk-Arg-Gly-Leu (10 micrograms/ml). Immunostaining was not affected by preincubation of the antiserum with Met-enkephalin (10 micrograms/ml), Leu-enkephalin (10 micrograms/ml) and Met-enkephalin-Arg-Phe (20 micrograms/ml). Out of the three precursors for a variety of opioid peptides throughout the body, i.e. preproenkephalin A, preproopiomelanocortin and preproenkephalin B, only preproenkephalin A contains Met-Enk-Arg-Gly-Leu.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1984

Light and electron microscopic immunocytochemistry of neurotensin-like immunoreactive neurons in the rat hypothalamus.

Neurotensin-like immunoreactive neuronal perikarya, fibers and terminals in the rat hypothalamus, particularly in the arcuate nucleus, the paraventricular nucleus and the median eminence, were investigated by light and electron microscopic immunocytochemistry. The main distributional areas of immunoreactive neuronal perikarya were found to be the arcuate nucleus, the periventricular nucleus and the paraventricular nucleus by light microscopic immunocytochemistry. Immunoreactive neuronal perikarya showed a characteristic distributional pattern in the arcuate nucleus. In the paraventricular nucleus they were distributed in both the magnocellular and parvocellular portions. A large number of immunoreactive terminals were observed throughout the external layer of the median eminence, particularly its lateral portion. A moderate number of immunoreactive terminals were also observed in the internal layer of the median eminence. By electron microscopic immunocytochemistry immunoreactive neuronal perikarya both in the arcuate and paraventricular nuclei showed generally well-developed cell organelles such as mitochondria, r-ER, and Golgi complex. In addition, immunoreactive dense granules were dispersed throughout the perikarya. A large number of immunoreactive terminals containing immunoreactive dense granules, clear vesicles and mitochondria were observed in the vicinity of pericapillary spaces of the external layer of the median eminence. This observation strongly suggests that neurotensin-like immunoreactive substance is released into the portal capillaries.

Animals↗
PubMed1984

Gastrin-releasing peptide immunoreactivity in medullary thyroid carcinoma.

Two cases of gastrin releasing peptide (GRP)-producing medullary thyroid carcinoma are presented. Immunohistochemical examination revealed the presence of GRP-like immunoreactivity (IR-GRP) in the primary tumor tissues. High concentration of IR-GRP was also demonstrated in extracts of the primary tumors by radioimmunologic means with use of a GRP-specific antiserum. Chromatographic analysis showed that the immunoreactivity was composed of at least two molecular forms: one behaved as synthetic porcine GRP on Sephadex G-50 gel filtration and the other as porcine GRP (14-27), a C-terminal active fragment of GRP. The IR-GRP was shown not to be attributed to bombesin-like immunoreactivity. Substance P-like immunoreactivity was not detected in the tumor tissues by either immunohistochemical or radioimmunologic means. This is, as far as the authors are aware, the first finding of IR-GRP as an ectopic product in medullary carcinoma.

Calcitonin↗
PubMed1984

[Motilin-like immunoreactivity in the canine pituitary and pineal glands--a histochemical study].

Motilin-like immunoreactivity in the canine pituitary and pineal glands shown by radioimmunoassay was re-investigated by histochemistry using anti-porcine motilin sera. Immunostaining of duodenal Mo cells was examined as a control. Tissues were fixed in Bouin's fluid and embedded in paraffin. Sternberger's peroxidase anti-peroxidase method was employed for histochemical reaction. Three lots of anti-motilin sera raised in rabbits ( R1104 , R1105 , R1106 ) and one lot of anti-motilin serum raised in a guinea pig ( GP2803 ) were used. An absorption test of the immunohistochemical reaction was performed using motilin (Mo 1-22), N-terminal fragment (Mo 1-17), or C-terminal fragment (Mo 7-22). The results obtained were summarized as follows: In the pituitary gland, endocrine cells showing motilin-like immunoreactivity were localized in the pars distalis and pars intermedia. In the pineal gland, pinealocytes showed no motilin-like immunoreactivity. Pituitary endocrine cells were strongly stained with two lots of anti-motilin sera ( R1104 , R1105 ). No distinct reaction was demonstrated with two other anti-motilin sera ( R1106 , G2803 ). The minimum concentration of antigens required for absorption of the immunohistochemical reaction was determined by their doubling-dilution. When R1105 anti-serum (1:1000) was pre-incubated with Mo 1-22, immunostaining of duodenal Mo cells re-appeared at a concentration of 0.1 X 2(-8) g/l, whereas pituitary endocrine cells remained unstained at a concentration of 0.1 X 2(-10) g/l. Using Mo 7-22, immunostaining of pituitary endocrine cells was absorbed up to a concentration of 0.1 X 2(-14) g/l, whereas duodenal Mo cells were positively stained at a concentration of 0.1 X 10(-6) g/l.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1984

Distribution and projections of neurons with immunoreactivity for both gastrin-releasing peptide and bombesin in the guinea-pig small intestine.

Bombesin-like and gastrin-releasing peptide (GRP)-like immunoreactivities were localized in nerves of the guinea-pig small intestine and celiac ganglion with the use of antibodies raised against the synthetic peptides. The anti-bombesin serum (preincubated to avoid cross reactivity with substance P) and the anti-GRP serum revealed the same population of neurons. Preincubation of the anti-bombesin serum with bombesin abolished the immunoreactivity in nerves while absorption of the anti-GRP serum with either bombesin or the 14-27 C-terminal of GRP only reduced the immunoreactivity. The immunoreactivity was abolished by incubation with GRP 1-27. Immunoreactive nerves were found in the myenteric plexus, circular muscle, submucous plexus and in the celiac ganglion. Faintly reactive nerve cell bodies were found in the myenteric ganglia (3.2% of all neurons) but not in submucous ganglia. After all ascending and descending pathways in the myenteric plexus had been cut, reactive terminals disappeared in the myenteric plexus, circular muscle (including the deep muscular plexus) and the submucous plexus on the anal side. After the mesenteric nerves were cut no changes were observed in the intestinal wall but the reactive fibres in celiac ganglia disappeared. It is deduced that GRP/bombesin-immunoreactive nerve cell bodies in myenteric ganglia project from the myenteric plexus to other myenteric ganglia situated further anally (average length 12 mm), anally to the circular muscle (average length 9 mm), anally to submucous ganglia (average length 13 mm) and external to the intestine to the celiac ganglia.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1984

Insulin, not C-peptide (proinsulin), is present in crinophagic bodies of the pancreatic B-cell.

We have obtained evidence by autoradiography and immunocytochemistry that mature secretory granules of the pancreatic B-cell gain access to a lysosomal compartment (multigranular or crinophagic bodies) where the secretory granule content is degraded. Whereas the mature secretory granule content shows both insulin and C-peptide (proinsulin) immunoreactivities, in crinophagic bodies only insulin, but not C-peptide, immunoreactivity was detectable. The absence of C-peptide (proinsulin) immunoreactivity in multigranular bodies, i.e., in early morphological stages of lysosomal digestion, was compatible with the ready access and breakdown of C-peptide and/or proinsulin by lysosomal degrading enzymes, while the insulin crystallized in secretory granule cores remained relatively protected. However, in the final stage of lysosomal digestion, i.e., in residual bodies where the secretory granule core material is no longer present, insulin immunoreactivity became undetectable. Lysosomal digestion thus appears to be a normal pathway for insulin degradation in the pancreatic B-cell.

Animals↗
PubMed1983

Leumorphin is a novel endogenous opioid peptide derived from preproenkephalin B.

Using synthetic leumorphin, we obtained antisera for leumorphin and set up two radioimmunoassays (RIAs) with different specificities. Gel exclusion chromatography coupled with the two RIAs showed the existence of a considerable amount of leumorphin-like peptide in water extracts from porcine neuro-intermediate pituitaries. Reverse phase high performance liquid chromatography revealed that leumorphin-like peptide in the water extracts was indistinguishable from synthetic leumorphin. These results along with potent opioid activity of leumorphin indicate that leumorphin is a novel endogenous opioid peptide derived from preproenkephalin B.

Animals↗
PubMed1983

Nerve elements containing Met-enkephalin-Arg6-Gly7-Leu8-like immunoreactivity in canine pancreas - a histochemical study.

Canine pancreas was examined by Sternberger's peroxidase-antiperoxidase method using an antiserum against Met-enkephalin-Arg6-Gly7-Leu8 (Met-Enk-Arg-Gly-Leu), an opioid octapeptide included in preproenkephalin A. Immunoreactive Met-Enk-Arg-Gly-Leu-containing nerve terminals with beaded appearance were demonstrated to be juxtaposed to small blood vessels of the exocrine and endocrine pancreas. Eighty-five out of 174 ganglion cell somas in the pancreas were immunopositive. The specific immunostaining was absorbed by preincubation of the antiserum (dilution, 1:2000) with Met-Enk-Arg-Gly-Leu (50 micrograms/ml), but not with Leu-enkephalin and Met-enkephalin (100 micrograms/ml).

Animals↗
PubMed1983

Coexistence of dopamine and neurotensin in hypothalamic arcuate and periventricular neurons.

The coexistence of dopamine and neurotensin in the same neuronal perikarya in the arcuate nucleus of the rat hypothalamus was examined by combined fluorescence histochemistry and immunohistochemistry on the same tissue sections and we obtained the evidence of the coexistence of two substances. The functional significance of those two substances for the prolactin release from the anterior pituitary was also briefly discussed.

Animals↗