Effect of 6-hydroxydopamine on neuropeptides in the rat female genitourinary tract

The occurrence and distribution of neuropeptide Y has been determined in the rat female genitourinary tract by radioimmunoassay and chromatographic analysis. Within the bladder, higher concentrations of neuropeptide Y were found in the trigone (48.8±5.2 pmol/g) than in the dome (36.0±2.1 pmol/g). In the genital tract, highest concentrations were identified in the vagina (41.4±2.1 pmol/g). Treatment of rats with 6-hydroxydopamine resulted in significant depletion of neuropeptide Y concentrations in both parts of the bladder, together with vagina, uterine horn and fallopian tube. No change was observed in the cervix, uterine body and ovary. Concentrations of vasoactive intestinal polypeptide were unaffected by treatment with 6-hydroxydopamine except in the area of the cervix where concentrations rose from 64.1±5.7 pmol/g to 133.6±15.1 pmol/g (p<0.05). There was a generalised, but statistically insignificant rise in substance P concentrations.     

Combined immunostaining of neurofilaments, neuron specific enolase, GFAP and S-100. A possible means for assessing the morphological and functional status of the enteric nervous system

Neurofilaments, part of the cytoskeletal network, and neuron specific enolase, a major enzyme in glycolysis, are both present in central and peripheral neurons. Glial fibrillary acidic protein and S-100, on the other hand, are soluble proteins which are found exclusively in the supportive cells of the nervous system, i.e. the glial cells. Examination was made, using immunocytochemistry, of all main areas of the gastrointestinal tract of three mammalian species, rat, pig and man. By applying serial tissue sectioning, it was possible to study the relative occurrences of the two neuronal markers in the same cell bodies and to examine the relationships of the neurons with the glial cells as revealed by the antibodies to glial fibrillary acidic protein and S-100. Both neurofilaments and neuron specific enolase were localised to an extensive system of enteric nerves, with the level of neuron specific enolase-immunoreactivity showing greater variability than that observed using antibodies to neurofilaments. Comparison of the occurrence of neuron specific enolase and neurofilament immunoreactivity in serially sectioned neuronal cell bodies revealed that a minor population stained only with antibodies to neurofilaments. The equivocal or absent neuron specific enolase-immunoreactivity in some perikarya may reflect variations in functional status within the nervous system. Glial fibrillary acidic protein- and S-100-immunoreactivities were confined to glial cells which, in this normal tissue, were always in close association with the neurons.(ABSTRACT TRUNCATED AT 250 WORDS)     

High concentrations of a novel peptide, neuropeptide Y, in the innervation of mouse and rat heart

A newly discovered bioactive peptide, neuropeptide Y (NPY), has been found in the innervation of the mouse and rat heart by immunocytochemistry, NPY-immuno-reactive nerves were very dense around the nodal tissues. They also surrounded the coronary arteries and arterioles and were found in close association with the cardiac muscle. The distribution of NPY-containing nerves paralleled that of noradrenergic fibers, demonstrated by the use of antibodies to the catecholamine-converting enzymes tyrosine hydroxylase and dopamine beta-hydroxylase. Furthermore, NPY was seen to be present in a proportion of intrinsic neurons mostly found in the atria and in close proximity to the nodal tissue. The concentrations of extractable NPY-immunoreactive material (about 150 pmol/g in whole mouse heart) by far surpasses those of the other peptides so far reported in the cardiac tissue. High performance liquid chromatography demonstrated the NPY immunoreactivity to elute in a single sharp peak, in an identical position to brain NPY.     

Morphological changes of sensory CGRP-immunoreactive and sympathetic nerves in peripheral tissues following chronic denervation

The morphological relationship between sensory and sympathetic nerves was studied in tissues of the eye and the oral cavity following chronic sympathetic or sensory denervation. Immunoreactivities for calcitonin gene-related peptide (CGRP) and tyrosine hydroxylase (TH) were used as indexes to assess the changes of the two nerve populations after denervation. Following surgical sympathectomy, a marked increase of CGRP-containing fibres was seen in all tissues studied, while TH-imunoreactive fibres were totally depleated. Conversely, after capsaicin treatment, an increase of TH-immunoreactive nerves was found in the same tissues, concomitant with a sharp decrease of CGRP-immunoreactive nerves. These changes were particularly evident in iridial stroma and around blood vessels in all tissue, where sensory and sympathetic nerves have a closely overlapping distribution pattern. The altered proportion of sensory peptide- and catecholamine-containing nerves following sympathetic and sensory denervation suggest that there is a reciprocal trophic influence between the two nerve subsets, possibly with the intervention of neurotrophic substances such as nerve growth factor. These results indicate a close interaction between sensory peptidergic and sympathetic nervous systems in peripheral organs.     

Fatty acid composition of the lipids of Puffinus tenuirostris (Temminck) in relation to its diet

The fatty acid composition of lipids isolated from the depot fat, stomach contents, and proventricular oil of adult and chick Puffinus tenuirostris (Temminck) has been analysed. The diet of both adults and chicks is almost exclusively derived from the euphausiid Nyctiphanes australis Sars, and an attempt was made to determine whether dietary lipid affects the composition of depot fat, and whether individual fatty acids in the stomachs and proventricular oil can be used as markers for the origin of the diet. An apparent selectivity in the deposition of fatty acids in the fat depots can be explained by the conversion of fatty alcohols, derived from the euphausiid wax ester, into fatty acids of equivalent chain length and unsaturation. Hexadecadienoic acid appeared to be the only possible marker fatty acid from the euphausiid, but wide variations in its level limits its usefulness as a reliable index of the diet of Puffinus tenuirostris.     

Specificity of compaction in meiotic chromosomes of the female Chinese hamster

This study describes the sequential alternation of compaction and decompaction in the chromosomes of the Chinese hamster oocyte from diakinesis to metaphase II. A series of micrographs show that the compact metaphase I chromosomes become greatly extended as they enter and pass through anaphase I. Once polarized, the presumptive oocyte chromosomes become exceedingly compact and form a tightly packed mass, each chromosome assuming contours to accomodate dovetailing with its neighbors, while the chromosomes consigned to the polar body remain extended and show signs of the incipient deterioration. Prior to ovulation, the chromosomes of the mass separate and begin to decompact, in part at least, by the previously postulated mechanism of uncoiling. Following ovulation, the chromosomes are greatly extended and, as the metaphase II complement, remain in that state until the advent of fertilization. — Evidence that the compaction patterns are ordered and chromosome specific is presented by observation of the two smallest chromosomes of the complement. At telophase I those chromosomes are markedly different in size and arm ratio; at metaphase II the differences are less pronounced and at mitotic metaphase the two smallest chromosome pairs are so similar in morphology as to be indistinguishable. It is proposed, therefore, that those two chromosomes differ in their fundamental morphology as revealed at the exceedingly compact state of telophase I oocyte chromosomes. Their subsequently established resemblance at mitotic metaphase may be due to allocycly on the part of one or both, resulting in two chromosomes of apparantly similar length and arm ratio.Supported by grants from the Institute of Child Health and Development of the National Institutes of Health, 5 RO1 HDO4846 and the Damon Runyan Foundation, DRG-907.Supported in part by CA-08748 from the Cancer Institute of the National Institutes of Health.     

Epilepsy and Oral Contraception

A controlled cross-over trial in 20 epileptic women, receiving regular anticonvulsant therapy showed that an oral contraceptive with a low oestrogen/ progestogen content had no significant effect on the average frequency of fits compared with identical dummy tablets.     

Acetazolamide and Sodium Bicarbonate in Treatment of Salicylate Poisoning in Adults

Ten adults suffering from salicylate overdosage were treated successfully with a combination of sodium bicarbonate and acetazolamide to exploit the increase in salicylate clearance which is known to occur in very alkaline urine. The advantages of the method include the absence of important complications and the small volume of fluid required.