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P Panula

Publications and source records attributed to P Panula.

At least 163 records · Page 9Linked to original sources
PubMed1986

Neuropeptides and NADPH-diaphorase activity in the ascending cholinergic reticular system of the rat.

A major group of cholinergic neurons is present in the midbrain and pontine tegmentum. These cells could be selectively stained using either monoclonal antibodies to choline acetyltransferase, the pharmacohistochemical acetylcholinesterase procedure, or reduced nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase histochemistry. Using these three techniques, the precise distribution of this cell group was determined. By combining these techniques with immunohistochemical staining for various neuropeptides, examples of peptide-cholinergic coexistence could be demonstrated in this cell group. Approximately 30% of these cholinergic neurons displayed substance P immunoreactivity. Most of these cells also showed corticotropin-releasing factor immunoreactivity and bombesin/gastrin-releasing peptide immunoreactivity. These results therefore provide evidence for the coexistence of various neuropeptides together with NADPH-diaphorase activity in the ascending cholinergic reticular system.

Acetylcholinesterase↗
PubMed1986

Histochemistry and function of bombesin-like peptides.

Bombesin-like peptides are a group of brain-gut peptides found in several neuronal groups in the central nervous system and in peripheral intrinsic gut neurons and sensory neurons. The SIF cells (small intensely fluorescent cells) of the sympathetic ganglia also contain immunoreactivity for these peptides. These peptides are present in some pulmonary endocrine cells and tumors originating from these cells. Chromatographic studies suggest that several different peptides, possibly originating from at least two different precursors, are present in mammalian tissues. Authentic amphibian peptide bombesin does not appear to be found in mammalian tissues. Functional studies indicate that these peptides may be involved in many important functions, including sensory transmission, regulation of central autonomic pathways, thermoregulation, secretion of pituitary hormones, gastric and pancreatic secretion, food intake and satiety.

Animals↗
PubMed1986

Light and electron microscopic immunocytochemistry of proenkephalin-derived peptides in septal neurons.

Specific antibodies against different opioid peptides derived from proenkephalin were used in light and electron microscopic studies to locate septal enkephalin-containing cells. Immunoreactive neurons were demonstrated only after pretreatment of the animals with colchicine. They were found in all three subdivisions of the lateral septal nucleus and in the ventral limb of the nucleus of the diagonal band. The medial septal nucleus and the dorsal limb of the nucleus of the diagonal band were devoid of immunoreactive cells. Electron microscopy showed intracellular enkephalin-like immunoreactivity with all antisera used in this study. The reaction was found in the cytoplasm, sometimes associated with the rough endoplasmic reticulum. Numerous enkephalin-immunoreactive nerve terminals and fibres were detected in the lateral septal nucleus, but axon terminals making contacts with enkephalin-immunoreactive neurons did not contain enkephalin-like immunoreactivity. The results suggest that some septal neurons synthesise proenkephalin. These cells may be either local interneurons or output cells to areas which receive innervation from the septal complex.

Animals↗
PubMed1985

Biochemical and immunohistochemical evidence for the presence of motilin in pig cerebellum.

The presence of motilin in rat and porcine cerebellum was investigated by using high performance liquid chromatography (HPLC) coupled with radioimmunoassay or immunohistochemistry. The antibodies used for this study were raised against synthetic gastrointestinal porcine motilin, which is, so far, the only known sequence of this peptide. The results obtained show the presence of a sharp peak of motilin-like immunoreactivity after HPLC of porcine cerebellum extracts, with an elution time corresponding to that of synthetic porcine motilin. Motilin-like immunoreactivity was also detected immunohistochemically in porcine cerebellum. However no motilin-like immunoreactivity was detected in rat cerebellum biochemically or immunohistochemically. This finding suggests that if a motilin-like neuropeptide is present in rat cerebellum, its molecular form differs from that present in porcine cerebellum.

Animals↗
PubMed1985

Histamine-immunoreactive endocrine cells in the adrenal medulla of the rat.

Histamine is widely distributed in various mammalian tissues and it has been shown that histamine is located in mast cells as well as in other structures. Biochemical evidence has been presented that histamine acts as a neurotransmitter in the central nervous system. Immunohistochemical studies have demonstrated the location of histamine-immunoreactive neuronal cells in both the central and peripheral nervous system. Biochemical studies have shown that histamine is present in the adrenal gland, while the location of histamine in the adrenal medulla is not known. There is pharmacological and biochemical evidence that exogenous histamine affects the catecholamine secretion of the adrenal medulla. The present study was undertaken to examine the location of histamine in the rat adrenal medulla by an indirect immunofluorescence method using a specific histamine antiserum. We now report the presence of histamine-immunoreactive endocrine cells in the adrenal medulla of the rat and suggest that histamine is located in the noradrenaline-secreting cells.

Adrenal Medulla↗
PubMed1985

The opioid octapeptide Met5-enkephalin-Arg6-Gly7-Leu8: characterization and distribution in rat spinal cord.

The regional quantitation, immunohistochemical localization and molecular heterogeneity of Met5-enkephalin-Arg6-Gly7-Leu8 were examined in rat spinal cord with a specific radioimmunoassay. A rostrocaudal gradient in Met5-enkephalin-Arg6-Gly7-Leu8 content was observed; the highest levels occurred in sacral cord. Dorsal cord content was higher than that of ventral cord at all spinal segments. Immunohistochemical staining supported and refined the latter observation: a dense network of perikarya and fibers was found in Laminae I and II of the dorsal horn. Cell bodies were frequently observed in lamina IV. Additional terminals were seen around the central canal and in the ventral gray matter, often outlining perikarya of motor neurons. Total Met5-enkephalin-Arg6-Gly7-Leu8 immunoreactivity could be fractionated into two main components using gel filtration chromatography. Nearly half of the total immuno-reactivity eluted as a high molecular weight peptide; the other half which co-eluted with Met5-enkephalin-Arg6-Gly7-Leu8 was further identified to be authentic Met5-enkephalin-Arg6-Gly7-Leu8 on reverse phase high pressure liquid chromatography. The present data, in conjunction with our previous study of Met5-enkephalin and Met5-enkephalin-Arg6-Phe7 indicates that all opioid peptides derived from preproenkephalin A are present in spinal cord and most likely are stored in the same neurons. Immunohistochemical localization of Met5-enkephalin-Arg6-Gly7-Leu8 in dorsal and ventral cord suggest a role for this peptide in both sensory and motor integration.

Animals↗
PubMed1985

Histamine-immunoreactive cells in the superior cervical ganglion and in the coeliac-superior mesenteric ganglion complex of the rat.

Histamine-immunoreactive small cells were detected in the superior cervical ganglion and in the coeliac-superior mesenteric ganglion complex of the rat with a specific antiserum produced in rabbits. Most histamine-immunoreactive cells were arranged in clusters, often around small blood vessels. Solitary immunoreactive small cells were also observed and they were easily distinguished from mast cells. The principal nerve cells showed no immunoreactivity to histamine and no histamine-containing nerve fibers were detected in the ganglia by the present method. Due to close morphological similarities, it is concluded that the small immunoreactive cells observed in the present study represent small intensely fluorescent (SIF) cells first detected by formaldehyde-induced catecholamine fluorescence.

Animals↗
PubMed1985

GABA-modulin: a synaptosomal basic protein that differs from small myelin basic protein of rat brain.

GABA-modulin, a basic protein that allosterically inhibits the high-affinity binding of GABA to its recognition sites, has been extracted and purified from the synaptosomal fraction of rat brain where it represents approximately 0.5% of the total synaptosomal proteins. GABA-modulin has characteristics in common to the class of highly basic proteins isolated from myelin, in particular to the rat small myelin basic protein (SMBP). However, GABA-modulin is located selectively in synaptosomes, whereas the SMBP is located in myelin. Moreover, synaptosomal GABA-modulin is different from SMBP in amino acid composition (it contains more Glx and Lys and fewer Arg residues) and in apparent molecular weight (17,000 and 15,000 for GABA-modulin and SMBP, respectively). Synaptosomal GABA-modulin fails to bind [3H]muscimol per se but noncompetitively inhibits (IC30 approximately 0.5 microM) the binding of [3H]muscimol to purified synaptic membranes. Cyanogen bromide treatment generated a 13,000 MW major fragment from both SMBP and GABA-modulin. These two fragments were compared and showed differences in amino acid composition and sequence. Moreover, the peptide maps generated from GABA-modulin and SMBP by trypsin and staphylococcal V8 protease digestion are different. The high concentration of GABA-modulin in synaptosomal membranes, its high potency in the inhibition of GABA binding, and its neuronal specificity suggest that GABA-modulin plays an important role in neuronal membrane function linked to the modulation of GABA and perhaps other neurotransmitter receptors.

Amino Acids↗
PubMed1985

Histamine-containing peripheral neuronal and endocrine systems.

An immunohistochemical method was developed to detect histamine in tissues. The aim of this study was to reveal the cellular stores of histamine in the gastrointestinal tract, pituitary, and adrenal gland. Histamine-containing nerve fibers were found in both rat and guinea pig gut. The origin of at least some of these fibers in the rat ileum was the submucous ganglion cell layer. In the rat stomach, numerous enterochromaffin-like cells exhibited histamine immunofluorescence, and endocrine cells in the ileum and jejunum contained histamine. Only mast cells contained histamine in the neurohypophysis. A large number of process-bearing cells in the guinea pig but not in the rat adrenal medulla contained histamine. The study shows that histamine is present in peripheral nerves and endocrine cells in addition to mast cells, and may function as a neurotransmitter or hormone.

Adrenal Glands↗
PubMed1985

Are Phe-Met-Arg-Phe-NH2 immunoreactive peptides endacoids modulating opiate antinociception?

Phe-Met-Arg-Phe-NH2 (FMRF-NH2) was initially isolated from the macrocallista nimbosa clam and subsequently existence of FMRF-NH2-like immunoreactivity (FMRF-NH2-IR) was detected in mammalian CNS. Due to the structural similarity between FMRF-NH2 and the C-terminal extended form of met5-enkephalin, met5-enkephalin-arg6-phe7 (YGGFMRF), a possible interaction between these two peptides was explored. FMRF-NH2 injected intrathecally decreases the antinociceptive action of YGGFMRF or morphine. However, the FMRF-NH2-IR present in rat and bovine brains differs from FMRF-NH2. Intrathecally injected FMRF-NH2-IR partially purified from bovine brain reduces YGGFMRF antinociception. The antagonism elicited by FMRF-NH2 can be reversed by proglumide, which was reported to act as a CCK antagonist. In order to characterize the biological profile of FMRF-NH2-IR, the effect of proglumide and of the FMRF-NH2 antibody on morphine analgesia was tested. Both the IgG isolated from FMRF-NH2 antiserum and proglumide were found to potentiate the morphine analgesia. The results taken together suggest that endogenous FMRF-NH2-IR modulates opioid antinociception; perhaps by acting as an endogenous naloxone.

Animals↗
PubMed1984

Spinal cord serotonin: a biochemical and immunohistochemical study following transection.

The serotonin (5-HT) content of rat spinal cord was studied following complete cord transection, transverse hemisection and rhizotomy by high pressure liquid chromatography-electrochemical detection (HPLC-EC) chromatography and immunohistochemically with rabbit anti-5-HT antiserum. Spinal cord 5-HT decreased but did not disappear after complete cord transection when studied 5 or 10 days after lesioning. Indeed the indole content 5 or 10 days after section were similar. Below the transection 5-HT-like immunoreactive neuronal elements were present, appeared normal but were significantly reduced compared with control cord. Although neuronal fibers were present after transection, no immunoreactive neuronal cell bodies were observed. The neuronal elements remaining after transection were capable of synthesizing and metabolizing 5-HT as evidenced by elevated 5-HT and decreased 5-hydroxyindoleacetic acid (5-HIAA) after inhibition of monoamine oxidase. Complete cord transection resulted in a fall of 5-HT in the ventral roots suggesting that they contain efferent 5-HT elements that originate above the transection. Rhizotomy plus cord transection did not change cord indole content more than transection alone demonstrating that the indoles that remain in the cord after transection did not originate from peripheral afferent 5-HT neurons. Hemitransection resulted in partial loss of immunoreactive neuronal elements on the cut side, but 5-HT-like immunoreactive nerve fibers were observed crossing within the cord from the intact side by the spinal canal. Analysis of indole content in the hemitransected cord were consistent with crossing of 5-HT fibers within spinal segments. Our studies, taken together with reports by other laboratories, support the notion that significant 5-HT elements remain in the spinal cord after transection. These elements appear normal morphologically and biochemically.

Animals↗
PubMed1984

Comparative distribution of bombesin/GRP- and substance-P-like immunoreactivities in rat hypothalamus.

Immunohistochemical localization of bombesin/gastrin-releasing peptide ( GRP )-like immunoreactivity (BN/ GRP -LI) and substance P-like immunoreactivity (SP-LI) in consecutive sections of rat hypothalamus was studied. Bombesin/ GRP -like immunoreactivity in the hypothalamus was partially characterized by gel filtration chromatography followed by radioimmunoassay. In the hypothalamus, SP-LI was more widely distributed than BN/ GRP -LI. Only the anterior and medial parvocellular parts of the nucleus paraventricularis and the nucleus suprachiasmaticus contained numerous cell bodies which exhibited BN/ GRP -LI. Neurons in these areas did not exhibit SP-LI. In contrast, cell bodies exhibiting SP-LI were numerous in the nucleus preopticus medialis and lateralis, nucleus anterior, nucleus ventromedialis and dorsomedialis, nucleus lateralis, nucleus arcuatus, and nucleus premamillaris ventralis and dorsalis. Only occasional cell bodies in these areas exhibited BN/ GRP -LI. It is concluded that the neuronal systems in the hypothalamus containing BN/ GRP -LI and SP-LI are separate, though the terminal fields in many areas overlap. Two peaks of BN/ GRP -LI were detected after gel filtration chromatography from extracts of the rat nucleus paraventricularis. The high molecular weight form coeluted with synthetic GRP (1-27), and the small molecular weight form eluted after synthetic bombesin. Thus, the endogenous BN/ GRP -LI is probably not authentic bombesin.

Animals↗
PubMed1984

An immunohistochemical study on the location of GABAergic neurons in rat septum.

Antisera against L-glutamate decarboxylase (GAD), the synthesizing enzyme of gamma-aminobutyric acid (GABA) were used to locate GABAergic neurons and nerve terminals in the septal complex of the rat by using the peroxidase-antiperoxidase method. Varying densities of immunoreactive terminals were observed in saline-treated rats but nerve cell bodies were only demonstrated after interventricular or intraseptal injections of colchicine. Small and medium-sized GAD-positive neurons were found in lateral septal nuclei, the largest number of these cells being in the pars dorsalis, and in the bed nucleus of the stria terminalis. Several GAD-immunoreactive neurons were located in the medial septal nucleus and the nucleus of the diagonal band of Broca (DB), where the cells were larger in the ventral than dorsal parts of the region. In the medial septal nucleus and in DB the GAD-positive cell bodies were distributed similarly to cholinergic neurons. Large GAD-positive neurons were also found in the septofimbrial nucleus. Intense immunoreactivity in nerve terminals was observed in the lateral septal nucleus, around the island of Calleja magna, between the DB and nucleus accumbens, and in the septofimbrial and triangular septal nuclei. In contrast, the medial septal nucleus, the DB, and the bed nucleus of the stria terminalis only showed weak to moderate immunoreactivity. These results provide direct morphological evidence for the presence of neurons capable of synthesizing GABA in septal nuclei. We suggest that there are two different GABAergic neuronal systems operating in the septum: a population of small cells in the lateral septal nucleus and a group of large cells in the medial septum and DB.

Animals↗
PubMed1984

The lacrimal glands of the rat and the guinea pig are innervated by nerve fibers containing immunoreactivities for substance P and vasoactive intestinal polypeptide.

Two neuropeptides, substance P and vasoactive intestinal polypeptide, have been shown to increase secretion of exocrine glands. We have studied immunohistochemically the intra- and exorbital lacrimal glands of the rat and the guinea pig for the presence of substance P-like and vasoactive intestinal polypeptide-like immunoreactive (SPLI and VIPLI, respectively) nerve fibers. Both SPLI and VIPLI nerve fibers were found surrounding glandular acini, secretory ducts and blood vessels. Their distribution, however, was uneven. The SPLI fibers predominated around the ducts whereas VIPLI fibers predominated around acini. The results suggest that the two neuropeptides may both regulate the lacrimal secretion, but they may have two different sites of actions because they prevail in different locations.

Animals↗
PubMed1984

Location of substance P-, bombesin-gastrin-releasing peptide, [Met5]enkephalin- and [Met5]enkephalin-Arg6-Phe7-like immunoreactivities in adult human sympathetic ganglia.

Indirect immunofluorescent methods were used to study peptides in human paravertebral sympathetic ganglia. [Met5]enkephalin, [Met5]enkephalin-Arg6-Phe7 and bombesin-gastrin-releasing peptide-like immunoreactivities were localized in varicose nerve fibers, which often formed basket-like networks around principal ganglion cells. Substance P-like immunoreactivity appeared frequently as solitary varicose nerve fibers and occasionally as networks. No immunolabeled cell bodies were discovered with any of the antisera used, including antibodies raised against molluscan cardioexcitatory peptide Phe-Met-Arg-Phe-NH2. The results demonstrate the presence of peptides within nerve fibers and terminals but not cell bodies of human paravertebral sympathetic ganglia. The localization suggests that the peptides have neurotransmitter or neuromodulator roles in the ganglia.

Enkephalin, Methionine↗
PubMed1984

Immunohistochemical evidence for epinephrine-containing retinal amacrine cells.

The enzyme for the synthesis of epinephrine, phenylethanolamine-N-methyltransferase, has been localized, by an indirect immunofluorescent staining method, to a subpopulation of amacrine cells in the rat retina. The immunoreactive cells are located primarily in the inner nuclear layer and send a single process to the inner plexiform layer. Most of the immunoreactivity is found in the center of the inner plexiform layer. A small percentage of immunoreactive cell bodies were found in the inner plexiform layer and occasionally cells were observed in the ganglion cell layer. These epinephrine-containing amacrine cells are morphologically distinct from the dopamine-containing amacrine cells previously described by formaldehyde fluorescence and we speculate from reports in the literature that epinephrine-containing amacrine cells may play a role in modulating the activity of dopamine-containing amacrine cells.

Animals↗
PubMed1984

Immunohistochemical localization of unique enkephalin sequences contained in preproenkephalin A in the guinea pig cochlea.

The guinea pig cochlea was studied for the presence of immunoreactivities to the four unique enkephalin sequences contained in the preproenkephalin A. The antisera to Met-enkephalin-Arg6-Phe7 and Met-enkephalin-Arg6-Gly7-Leu8 were used as highly specific markers for the preproenkephalin A. Contrary to Met-enkephalin and Leu-enkephalin, also included in the present study, these two peptide sequences are not contained in pro-opiomelanocortin or preproenkephalin B (prodynorphin). All the four different antisera showed identical localization for the four peptide sequences, suggesting their coexistence in the same nervous pathway. Specific immunofluorescence was found in intraganglionic spiral bundle, inner spiral bundle, tunnel spiral bundle and in association with inner hair cells. The nerve fibers were thin and varicose, suggesting that most, if not all, of them were unmyelinated. Their localization indicates that the unique enkephalin sequences contained in preproenkephalin A are present in the cochlear efferent pathway to the inner hair cell region.

Animals↗