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Biomedical subjects

F Sundler

Publications and source records attributed to F Sundler.

At least 433 records · Page 24Linked to original sources
PubMed1981

Evidence for the presence of pro-gamma-melanotropin, the NH2-terminal fragment of the corticotropin-beta-lipotropin precursor, in corticotropin-producing tumours.

Five corticotropin-producing tumours were examined for peptides related to the corticotropin-beta-lipotropin precursor. Two were basophil pituitary adenomas and three were bronchial carcinoids. The cells of the two pituitary adenomas stained with antisera against beta-endorphin and against pro-gamma-melanotropin, the NH2-terminal fragment of the corticotropin-beta-lipotropin precursor, but not with antisera against alpha-melanotropin or beta-lipotropin. The corticotropin-storing tumor cells of the bronchial carcinoids stained with antisera against beta-endorphin, beta-lipotropin or pro-gamma-melanotropin. Only one of the three bronchial carcinoids contained cells reacting with the antiserum against alpha-melanotropin. Although the two types of corticotropin-storing tumours (pituitary adenoma and bronchial carcinoid) differed with respect to beta-lipotropin content, the over-all picture indicates that the proteolytic processing of the corticotropin precursor proceeds along similar lines in tumour cells and in pituitary corticotrophs. An acetic acid extract of one of the bronchial tumours was subjected to gel chromatography and immunochemical analysis of material related to pro-gamma-melanotropin. The immunoreactive material displayed a considerable size heterogeneity, with the predominant components having a molecular weight larger than that of authentic pro-gamma-melanotropin.

Adenoma, Basophil↗
PubMed1981

Substance P-like immunoreactivity in the nervous system of hydra.

Using immunocytochemistry we find substance P-like material in nerve cells of hydra. These nerve cells are situated in the ectoderm of the basal disk and tentacles. Radioimmunoassay of hydra extracts gives dilution curves parallel to that of synthetic substance P, from which it can be calculated that one animal contains at least 0.6 fmol substance P-like immunoreactivity. After chromatography on Biogel P-100, the substance P-like immunoreactivity elutes as a peak in the void volume and a peak at the position of synthetic substance P.

Animals↗
PubMed1981

Enkephalin-immunoreactive nerve fibers in the feline genito-urinary tract.

Besides the classical neurotransmitters acetylcholine and norepinephrine the genito-urinary tract contains also neuropeptides. The distribution of substance P- and VIP-containing nerve fibers have earlier been described. Also enkephalin-immunoreactive nerve fibers occur in the male and female genito-urinary organs of the cat. The nerves are more numerous in male than in female genital tract. The prostatic gland and vas deferens receive the largest supply. In the female genital tract the enkephalin-immunoreactive nerve fibers are regularly seen in the smooth muscle layer of the cervix. Of special interest is the rich occurrence of the enkephalin nerve fibers among th nerve cell bodies in the para-urethral and cervical ganglia supporting the view that enkephalin may play a neuromodulating role.

Animals↗
PubMed1981

Neurotensin-like immunoreactivity in the nervous system of hydra.

Neurotensin-like immunoreactivity is found in nerve fibers present in all body regions of hydra. The nerve fibers are especially numerous in the ectoderm at the bases of the tentacles and in the ectoderm at a site just above the foot. Radioimmunoassays of acetic-acid extracts of hydra, using various region-specific antisera towards mammalian neurotensin, show the presence of multiple neurotensin-related peptides. The amounts of these peptides vary between 1 and 350 pmol per gram wet weight. Gel filtration on Sephadex G-25 reveals a fraction of neurotensin-like peptides that crossreact equally well with an antiserum directed against sequence 1-8 and an antiserum directed against sequence 6-13 of neurotensin. This fraction elutes also at the position of neurotensin and might closely resemble the mammalian peptide. A fraction eluting with the void volume crossreacts preferentially with antisera directed against sequences 1-8 and 10-13 of neurotensin. Several components of apparent lower molecular weight than neurotensin crossreact preferentially with an antiserum against sequence 10-13. These last peptides represent the major portion of the neurotensin-like peptides in hydra.

Animals↗
PubMed1981

Perivascular substance P: occurrence and distribution in mammalian pial vessels.

Nerve fibres containing immunoreactive substance P (SP) were demonstrated in the wall of cerebral blood vessels of several mammalian species. Pial arteries of cat and guinea-pig were richly supplied with SP nerve fibres, while those of rat, rabbit, pig, and man had a moderate number. SP fibres were more numerous in pial vessels belonging to the rostral parts of the circle of Willis as compared to more caudally located blood vessels. In cat and guinea-pig, blood vessels in the choroid plexus were surrounded by few SP nerve fibres; also spinal cord blood vessels of cat contained few such fibres.

Animals↗
PubMed1981

A case of papillary-cystic epithelial neoplasm of the pancreas.

A 16-year-old girl presented with a left-sided abdominal mass. X-ray examination and computed tomography disclosed a well-defined tumor close to the tail of the pancreas, stretching the pancreatic branches from the splenic artery as demonstrated by arteriography. Ultrasonography suggested a partly cystic character. Cytologic fine-needle biopsy, histopathological and electron microscopical examination disclosed a cysto-papillary tumor, probably benign, and of an exocrine, ductular origin, and with pseudo-cystic areas similar to those found in adenoid cystic carcinoma of salivary glands. Immunohistochemistry did not demonstrate the presence of polypeptide hormones. The patient is without signs of tumor recurrence 18 months after operation.

Adolescent↗
PubMed1981

VIP nerve fibres around peripheral blood vessels.

By immunocytochemistry nerve fibres containing vasoactive intestinal polypeptide (VIP) were demonstrated around many peripheral blood vessels in the cat. Such nerve fibres were particularly numerous around arteries in the upper respiratory, gastrointestinal and genito-urinary tracts. They were less numerous around large arteries and veins and seemed to be absent from the blood vessels in liver, spleen and kidney. VIP nerve fibres were few around blood vessels in skeletal muscle and absent in coronary arteries. Administration of VIP in vitro relaxed all arteries tested provided they had been given an increased tone, for instance by preincubation with PGF2 alpha. It is likely that VIP in vascular nerve fibres may participate in the regulation of systemic and local blood flow.

Animals↗
PubMed1981

GIP-like immunoreactivity in glucagon cells. Interactions between GIP and glucagon on insulin release.

In the present study the cellular and subcellular distribution of immunoreactive glucagon and GIP (gastric inhibitory polypeptide) were studied in the mouse. Furthermore, the effects of pure GIP and glucagon on basal and stimulated insulin secretion were investigated. Immunohistochemistry revealed that immunoreactive GIP occurred in the pancreatic glucagon cells and in endocrine cells, also displaying glucagon immunoreactivity, scattered along the small and large intestines. Electron immunocytochemistry revealed that the GIP-like material and glucagon coexisted in the secretory granules of the pancreatic glucagon cells. Pure porcine GIP and glucagon both stimulated basal insulin release. When equipotent doses of the peptides were given together, the two peptides antagonized each other's effect. Both peptides potentiated glucose- and carbachol-induced insulin release. When equipotent doses of the two peptides were given together prior to the administration of each of these secretagogues their effects on insulin release were additive.

Animals↗
PubMed1981

Distribution and motor effect of VIP in female genital tract.

The distribution and concentration of vasoactive intestinal polypeptide (VIP) in different parts of the female genital organs from various species (cat, goat, pig, rabbit, rat, and guinea pig) were studied by means of immunohistochemistry and immunochemistry. In addition, the effect of VIP on the mechanical activity of uterine muscle was investigated in vitro. VIP immunoreactive nerve fibers innervating vessels and smooth muscle cells were fairly numerous in the genital organs of the cat and goat and less numerous in the pig, rabbit, rat, and guinea pig. In all species studied, VIP-containing nerves were most numerous in the cervix. The tissue concentration of VIP measured by immunochemistry was in agreement with the immunohistochemical findings. VIP inhibited the mechanical uterine activity in the cat, goat, pig, and rabbit, whereas only minimal effects were obtained in the rat and guinea pig. This difference between the species corresponded to the number of VIP-containing nerves in the uterine muscle. The data support the hypothesis that VIP may play a physiological role in the local nervous control of the uterine mechanical activity.

Animals↗
PubMed1981

Peptide containing nerves in the nasal mucosa.

Numerous nerve fibres containing vasoactive intestinal peptide (VIP), substance P (SP) or immunoreactive avian pancreatic polypeptide (APP) occur in the nasal mucosa of several mammals, including man. Generally, the nerve fibres are distributed around small blood vessels and seromucous glands. In addition, SP containing fibres can be seen in the nasal epithelium. The pterygopalatine ganglion contains acetylcholinesterase (AChE) positive nerve cell bodies together with VIP and SP containing ones. After exposure to colchicine it could be shown that the VIP and SP containing nerve cell bodies also were positive for AChE. VIP and SP are potant mediators of atropine resistent vasodilatation in the mucosa. The physiological effects of APP are not known.

Animals↗
PubMed1980

Relaxation of human female genital sphincters by the neuropeptide vasoactive intestinal polypeptide.

Vasoactive intestinal polypeptide (VIP), a recently recognized neuropeptide with a putative transmitter function, has been demonstrated in nerves in the female genital tract. The highest density is in the smooth, muscle of the isthmus of the fallopian tubes and of the uterine cervix. The motor effect of VIP has been tested in vitro of smooth muscle from the isthmus and the uterine cervix. Both preparations responded to VIP with a concentration-dependent reduction in motor activity.

Adult↗
PubMed1980

VIP occurs in intrathyroidal nerves and stimulates thyroid hormone secretion.

Vasoactive intestinal polypeptide (VIP) is known to have powerful effects on the secretion from several endocrine and exocrine glands, and occurs in nerves with a ubiquitous distribution in the body. This infers that neuronal VIP may be a regulator of such secretion, and there is evidence that it is involved in the regulation of exocrine pancreatic function. Previous studies have shown that adrenergic and cholinergic nerves participate in the regulation of thyroid hormone secretion. We describe here combined immunohistochemical and immunochemical studies which show that the thyroid of several species is supplied with VIP-containing nerve fibres that surround blood vessels and run between and along thyroid follicles and that in the mouse neuronal VIP participates in the regulation of thyroid hormone secretion through a mechanism that is mediated by cyclic AMP.

Animals↗
PubMed1980

Vasoactive intestinal peptide (VIP) occurs in nerves of the pineal gland.

Nerves staining with antibodies against vasoactive intestinal peptide (VIP) were detected in the pineal gland of the rabbit, cat and pig. VIP nerves were numerous in the cat but few in the rabbit and pig. A particularly rich VIP nerve supply was noted in the pineal stalk of the cat. The nerves were predominantly located around small blood vessels. Occasionally, nerve fibres were seen in the glandular parenchyma without obvious relation to blood vessels.

Animals↗