Biomedical subjects

C Grothe

Publications and source records attributed to C Grothe.

66 records · Page 4Linked to original sources

PubMed1989

Basic fibroblast growth factor prevents ontogenetic neuron death in vivo.

Basic fibroblast growth factor (bFGF) is a mitogen and a potent neurotrophic protein for ciliary ganglionic (CG) neurons in vitro. Recombinant bFGF was administered to the chorionic-allantoic membrane of chick embryos during the period of ontogenetic neuron death in the cholinergic CG between embryonic days (E) 8 and E14. Neuronal losses in untreated chicks and in embryos that received the vehicle only (phosphate-buffered saline plus cytochrome c) amounted to 44%. Basic FGF permitted the survival of 87% of the neurons present at E8. There were no apparent differences in the size and number of non-neuronal cells in CG. These data add to the increasing body of evidence that bFGF is an important multifunctional growth factor with a neurotrophic capacity.

Animals↗

PubMed1989

A role of basic fibroblast growth factor for rat septal neurons.

The in vitro and in vivo relevance of basic fibroblast growth factor (bFGF) for rat septal neurons was studied and compared with the effects of nerve growth factor (NGF). Implantation of gel foam soaked with saline, NGF or bFGF following fimbria fornix (FF) transection in adult rats showed that after 4 weeks the neuronal death in the medial septum of saline-treated rats (87% as compared to the unlesioned side) was reduced by NGF- or bFGF-treatment (NGF 0.3 micrograms: 71%; NGF 20 micrograms: 54%; bFGF 8 micrograms: 68%). These results indicate that both NGF and bFGF are able to sustain neurons in the medial septum after FF transection. Moreover, choline acetyltransferase (ChAT)-immunocytochemistry revealed that rescued neurons comprise a large proportion of the cholinergic population. In cultured embryonic rat septal neurons seeded at high densities both NGF and bFGF significantly enhanced ChAT activity (7.5- and 3-fold, respectively) without affecting cell survival. In low density cultures both neurotrophic proteins increased the survival after 4 days. The portions of cholinergic and GABAergic neurons did not change after NGF- and bFGF-treatment (acetylcholinesterase cytochemistry, anti-GABA immunocytochemistry). These results show that i) NGF and bFGF promote survival of embryonic septal cholinergic and GABAergic neurons and may enhance ChAT activity, and ii) bFGF is a potent trophic factor for septal neurons in vivo and in vitro.

Animals↗

PubMed1989

Basic fibroblast growth factor promotes in vitro survival and cholinergic development of rat septal neurons: comparison with the effects of nerve growth factor.

The effects of basic fibroblast growth factor and nerve growth factor on survival and transmitter expression of cultured rat embryonic (E18) septal neurons were studied. Two different culture media were used: (i) a horse serum-containing Leibowitz L-15 medium and (ii) a serum-free N1-supplemented Dulbecco's modified Eagle's medium. Addition of basic fibroblast growth factor to either culture medium enhanced neuronal survival in low density cultures after 4 days. The effects of basic fibroblast growth factor were dose-dependent and blocked by anti-basic fibroblast growth factor antibodies. In serum-containing L-15 medium nerve growth factor also promoted neuronal survival. Basic fibroblast growth factor and nerve growth factor supported neurons comprised both cholinergic and GABAergic subpopulations. The effects of basic fibroblast growth factor and nerve growth factor were not additive. In high density cultures using serum-containing L-15 medium survival of septal neurons was four times higher than in low density cultures after 4 days. Addition of basic fibroblast growth factor or nerve growth factor did not further augment neuronal survival in high density cultures. Maintenance of septal neurons at high density was not affected by antibodies to basic fibroblast growth factor and/or nerve growth factor. Addition of basic fibroblast growth factor or nerve growth factor to serum-containing L-15 medium at high cell density significantly enhanced choline acetyltransferase activity 3- and 7.5-fold, respectively, without affecting cell survival. In conclusion, next to nerve growth factor, basic fibroblast growth factor, which has been located in the hippocampal target area of septal neurons, appears to be another potent trophic factor for septal neurons.

Animals↗

PubMed1989

Immunocytochemical localization of basic fibroblast growth factor in bovine adrenal gland, ovary, and pituitary.

We studied the distribution of basic fibroblast growth factor (bFGF) immunoreactivity in bovine adrenal gland, ovary, and pituitary, using a polyclonal anti-bFGF antibody. In the adrenal gland, the inner layers of the capsule, the zona glomerulosa of the cortex, and the chromaffin cells of the adrenal medulla were intensely stained. In the ovary, follicular epithelial cells of growing follicles and granulosa cells of mature follicles showed strong bFGF-like immunoreactivity. Endocrine cells of the pituitary anterior and intermediate lobes displayed a positive immunoreaction. Blood vessels, including endothelial and smooth muscle cells, as well as stromal cells in all three organs studied, were not stained. This distribution pattern of bFGF immunoreactivity is only partially compatible with the established mitogenic role of this protein, and suggests a wider spectrum of bFGF functions.

Adrenal Glands↗

PubMed1988

Reciprocal age-dependent pattern of two neuronal markers, tetanus toxin and neuron-specific enolase, in postnatal rat sensory and sympathetic neurons.

Tetanus toxin (TT) and antibodies to neuron-specific enolase (NSE) were used to study the developmentally regulated expression of two neuronal markers in isolated and short-term cultured rat sensory and sympathetic neurons at different postnatal ages. The results show a reciprocal pattern of TT binding and NSE-immunoreactive neurons during postnatal maturation: there is a gradual transition from TT-positive, NSE-negative to TT-negative, NSE-positive phenotypic expressions. We conclude that TT may serve as a neuronal marker for newborn, anti-NSE antibodies as markers for adult neurons, and a combination of both for adolescent neurons.

Adrenergic Fibers↗

PubMed1988

Immunocytochemical demonstration of fibroblast growth factor in cultured chick and rat neurons.

The presence of fibroblast growth factor (FGF) was investigated by immunocytochemistry in cultured neuronal cells derived from the peripheral (PNS) and the central nervous system (CNS) of chick and rat embryos. Polyclonal antimouse FGF antibodies, which cross-react with basic and acidic FGF, were used in the peroxidase immunocytochemical staining method. FGF immunoreactivity was found in neurons. Staining intensity in chick and rat brain neuronal cells increased during the culture period, reached a maximum after 6-8 days, and subsequently declined. Embryonic chick ciliary and dorsal root ganglionic (DRG) neurons as well as DRG neurons from newborn rat displayed intense FGF immunoreactivity at 12 and 48 hr in culture. Nonneuronal cells were not stained. The data demonstrate for the first time that cultured neurons from the CNS and PNS contain FGF.

Animals↗

PubMed1988

Catecholaminergic nerves in the embryonic chick ovary: co-localization with beta 2-adrenoceptor-bearing steroidogenic cells.

The present study investigates the innervation of the embryonic chick ovary with regard to (i) development and compartmentalization of catecholaminergic nerves, and (ii) presence of adrenoceptors on steroidogenic target cells of catecholaminergic nerve terminals. Catecholaminergic nerve fibers visualized by glyoxylic acid-induced histofluorescence first appeared at embryonic day (E) 13. From E15 through E21 the density of fluorescent aminergic nerves increased markedly in parallel with the concentration of catecholamines and numbers of nerve bundles and single axons seen at the electron-microscopic level. Catecholaminergic nerves were confined to the ovarian medulla and closely associated with interstitial cells. Nerve terminals approached interstitial cells up to a distance of 20 nm and, in their majority, exhibited uptake of the false adrenergic transmitter 5-hydroxydopamine. Although adrenaline amounted to 14% of the total catecholamine content at E21, adrenaline immunoreactivity was only detected in adrenal chromaffin cells, but not in nerve fibers or cell bodies within the ovary. Interstitial cells structurally matured between E15 and E21 as documented by an increase of smooth endoplasmic reticulum and tubular mitochondria. Monoclonal antibodies mAB 120 and BRK 2 raised against avian beta 1- and mammalian beta 2-adrenergic receptors revealed the presence of beta 2-adrenoceptor-like immunoreactivity on the surface of interstitial cells, but not on any other cell type. The results are consistent with the notion of a dense adrenergic innervation of the embryonic chick ovarian medulla and its steroidogenic interstitial cells, and suggest the chick ovary as an excellent model for elucidating the functional role of a neural input to steroidogenic cells during development.

Animals↗

PubMed1987

Pharmacological effects of nerve growth factor and fibroblast growth factor applied to the transectioned sciatic nerve on neuron death in adult rat dorsal root ganglia.

Sciatic nerve transection performed on adult rats caused neuronal losses after 4 weeks in the L4-6 dorsal root ganglia (DRG) of 35% as compared to the unlesioned side. Nerve growth factor (NGF) administered at a single dose of 6000 Biological Units in silicone tubes fixed to the proximal nerve stump completely prevented these cell losses. Basic fibroblast growth factor (bFGF) also protected DRG neurons, but at the concentrations applied (6000 Trophic Units, tested on embryonic chick ciliary ganglion neurons), failed to maintain cell numbers identical to unoperated side. Our data indicate that NGF and bFGF protect adult sensory neurons from lesion-induced death. Preliminary results suggest that local accumulation of neurotrophic activities at the proximal nerve stump elicited by NGF and, possibly bFGF, might be involved in the beneficial effects of these proteins on the maintenance of axotomized sensory neurons.

Animals↗

PubMed1987

Neuron-enriched cultures of adult rat dorsal root ganglia: establishment, characterization, survival, and neuropeptide expression in response to trophic factors.

It is unknown whether adult dorsal root ganglion (DRG) neurons require trophic factors for their survival and maintenance of neuropeptide phenotypes. We have established and characterized neuron-enriched cultures of adult rat DRGs and investigated their responses to nerve growth factor (NGF), ciliary neuronotrophic factor (CNTF), pig brain extract (PBE, crude fraction of brain-derived neuronotrophic factor, BDNF), and laminin (LN). DRGs were dissected from levels C1 through L6 and dissociated and freed from myelin fragments and most satellite (S-100-immunoreactive) cells by centrifugation on Percoll and preplating. The enriched neurons, characterized by their morphology and immunoreactivity for neuron-specific enolase, constituted a population representative of the in vivo situation with regard to expression of substance P (SP), somatostatin (SOM), and cholecystokinin-8 (CCK) immunoreactivities. In the absence of trophic factors and using polyornithine (PORN) as a substratum, 60-70% of the neurons present initially (0.5 days) had died after 7 days. LN as a substratum did not prevent a 30% loss of neurons up to day 4.5, but it subsequently maintained DRG neurons at a plateau. This behavior might reflect a cotrophic effect of LN and factors provided by non-neuronal cells, whose proliferation between 4.5 and 7 days could not be prevented by addition of mitotic inhibitors of gamma-irradiation. CNTF, but not NGF, slightly enhanced survival at 7 days on either PORN or LN. No neuronal losses were found in non-enriched cultures or when enriched neurons were supplemented with PBE, indicating that non-neuronal cells and PBE provide factor(s) essential for adult DRG neuron survival. Proportions of SP-, SOM-, and CCK-immunoreactive cells were unaltered under any experimental condition, with the exception of a numerical decline in SP cells in 7-day cultures with LN, but not PORN, as the substratum. Our data, considered in the context of recent in vivo and vitro studies, suggest that a combination of trophic factors or an unidentified factor, rather than the established molecules NGF, CNTF, and BDNF, which address embryonic and neonatal DRG neurons, are required for the in vitro maintenance of adult DRG neurons.

Animals↗

PubMed1987

Cytochemical and biochemical characterization of neurosecretory material in the brain of an annelid, Ophryotrocha puerilis (Polychaeta).

In the brain of the protandric annelid Ophryotrocha, prominent axon terminals accumulate neurosecretory material in female-phase individuals. This material is not present in females after they have had social contact for 2 days and in males. After treatment with Formalin or glyoxylic acid, the axon terminals in isolated females are brightly fluorescent. The injection of reserpine into the coelomic cavity of such females prevents the development of fluorescence in the nerve endings. In an HPLC study of brains containing axon terminals filled with neurosecretory material, catecholamines were found to be present in large quantities. In specimens with empty axon terminals, the amount of catecholamines was significantly less. Thus the secretory material appears to contain catecholamines. The results presented suggest dopamine to be the major component of the neurosecretory material.

Animals↗

PubMed1985

Nerve growth factor and dexamethasone specify the catecholaminergic phenotype of cultured rat chromaffin cells: dependence on developmental stage.

Antibodies to epinephrine (E) and bovine phenylethanolamine N-methyltransferase (PNMT) have been used to monitor the regulation of the E- and PNMT-immunoreactive chromaffin cell phenotypes by dexamethasone (DEX) and nerve growth factor (NGF). The cells were isolated from 1-, 10- and 30-day-old (D1, D10 and D30) rat adrenal glands and grown for 4 days on a polyornithine substratum. DEX (10(-5)M) supported the survival of 90% of the cells from all postnatal ages studied. In contrast, only 45% (D1), 33% (D10) and 60% (D30) of the chromaffin cells had survived after 4 days in control cultures or when treated with NGF (100 ng/ml). Throughout this study numbers of E-immunoreactive cells were approximately 10% larger than those of cells stained by anti-PNMT antibodies irrespective of the treatments applied. 55% of the cells isolated at D1 and 79% of the cells at D10 were stained by anti-E antibodies. The proportion of E-positive cells was constant in D1 cultures carried for 4 days, while E-immunoreactive cells dropped to 63% in cultures from D10. At D1 and D10 DEX and NGF had opposite effects on the portions of E-positive cells, DEX increasing and NGF decreasing their relative numbers, 66% of the chromaffin cells isolated at D30 displayed E-specific immunoreactivity. DEX caused a significant increase (to 74%), while both NGF-treated and control cultures exhibited a decrease in the relative numbers of E-immunoreactive cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Medulla↗

PubMedDate not supplied

Patterns of epidermal growth factor receptor, basic fibroblast growth factor and transforming growth factor-beta3 expression in skin with chronic venous insufficiency.

Growth factors which act as signalling peptides through specific cell surface receptors are involved in functions such as cell proliferation, migration, and differentiation. Here, we report on alterations of the epidermal growth factor receptor (EGFR), basic fibroblast growth factor (bFGF) and transforming growth factor beta3 (TGF-beta3) expression patterns in the skin at various stages of chronic venous insufficiency (CVI). Thirty punch biopsies were taken from patients with CVI and growth factors or the growth factor receptor were detected by indirect immunofluorescence and immunoperoxidase techniques. EGFR, bFGF, and TGF-beta3 expression is strongly increased in the stroma of venous eczema and in leg ulcer skin, and to a lesser extent in the dermis of patients with lipodermatosclerosis. Venous eczema and lipodermatosclerosis epidermis show an elevated EGFR and bFGF synthesis throughout all strata. In the different CVI stages, telangiectases and reticular veins and pigmentation EGFR and bFGF staining are limited to the basal layer. We conclude that the alterations in the expression of EGFR, bFGF and TGF-beta3 precede changes in the affected skin within progressing stages of CVI. The exact mechanisms of growth factor involvement in the pathogenesis of venous ulceration remain to be resolved.

Aged↗