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M Fingerman

Publications and source records attributed to M Fingerman.

At least 37 records · Page 2Linked to original sources
PubMed1988

Comparative strategies of pigmentary regulation in invertebrates.

This brief survey of color change strategies among invertebrates has dealt mainly with the diversity encountered in three aspects of their pigment cell biology: (1) the types of chromatophores they possess, (2) the control of color changes by nerves or hormones if the chromatophores are not acting only as independent effectors and (3) the functions of the physiological color changes these animals exhibit. Of these three topics, much less is known about the last one, the functions of the color changes, than about the first two. There has been much hypothesizing about the functions of color changes and the advantages such changes presumably confer, but relatively few data have been generated to support the hypotheses.

Animals↗
PubMed1987

Distal retinal pigment of the fiddler crab, Uca pugilator: release of the dark-adapting hormone by methionine enkephalin and FMRFamide.

The neuropeptides methionine enkephalin and FMRFamide, when injected into intact fiddler crabs, Uca pugilator, produce dark adaptation of the distal retinal pigment. Furthermore, both neuropeptides stimulate release of distal retinal pigment dark-adapting hormone activity from the isolated eyestalk neuroendocrine complex. It is hypothesized that both neuropeptides, when injected into intact fiddler crabs, act only indirectly on the distal retinal pigment, by stimulating release of this dark-adapting hormone.

Acclimatization↗
PubMed1986

Effects of two tranquilizers, reserpine and chlorpromazine, on neurosecretory cells and the ovary of the fiddler crab, Uca pugilator.

Reserpine produced alterations in neurosecretory cell types I and II in the eyestalk, brain, and thoracic ganglion, most notably a decrease in the amount of stored neurosecretory material. The ovarian index decreased, but the oocyte area increased in the reserpinized crabs. Chlorpromazine did not produce any significant changes in the structure of cell types I and II. In spite of having a normal area, the oocytes in the chlorpromazine injected crabs were devoid of yolk. Neurosecretory cell type III showed no change.

Animals↗
PubMed1985

Localization of substance P-like, leucine-enkephalin-like, methionine-enkephalin-like, and FMRFamide-like immunoreactivity in the eyestalk of the fiddler crab, Uca pugilator.

The occurrence and distribution of substance P (SP)-like, methionine-(Met)- and leucine-(Leu)-enkephalin-like, and FMRFamide-like immunoreactivities were determined in the neuroendocrine complex of the eyestalk of the fiddler crab, Uca pugilator, by immunocytochemistry. SP-like immunoreactivity was found in the optic peduncle, sinus gland, medulla externa, medulla interna, lamina ganglionaris, and retinular cells. Met-enkephalin-like and Leu-enkephalin-like immunoreactivity was observed in most of the retinular cells, optic peduncle, sinus gland, medulla terminalis, and lamina ganglionaris. However, Met-enkephalin-like, but no Leu-enkephalin-like, immunoreactivity was seen in the medulla terminalis X-organ. FMRFamide-like immunoreactivity could be seen in all parts of the eyestalk except in the sinus gland, lamina ganglionaris, and retinular cells. FMRF-amide-like activity was especially strong in the three chiasmatic regions connecting the optic ganglia. The possibility that these four peptides may function as neuroregulators in the fiddler crab is discussed.

Animals↗
PubMed1985

Enzyme-linked immunosorbent assay of black pigment dispersing hormone from the fiddler crab, Uca pugilator.

An enzyme-linked immunosorbent assay was developed for black pigment dispersing hormone (BPDH) obtained from the fiddler crab, Uca pugilator. Immunoreactive BPDH, as high as 8.8 +/- 0.9 ng/50 microliters, was found in the hemolymph of crabs with dispersed black pigment. High potassium saline caused 4.5 +/- 0.4 ng immunoreactive BPDH to be released into the medium from isolated crab eyestalks in 5 min.

Animals↗
PubMed1984

Effect of naphthalene on color changes of the sand fiddler crab, Uca pugilator.

The polycyclic aromatic hydrocarbon, naphthalene, inhibited the melanin dispersion, which normally occurs in the fiddler crab, Uca pugilator, during the dark phase of its circadian rhythm of color change. Naphthalene produced this inhibition no matter whether the melanin was fully aggregated or more or less dispersed at the time of initial exposure. Inhibition of the circadian melanin dispersion does not appear to be due to a direct action of naphthalene on the melanophores. This inhibition was concentration-dependent with acute daily exposure. Naphthalene does not, however, inhibit melanin dispersion in response to a black background, indicating thereby that naphthalene-exposed crabs continue to synthesize melanin-dispersing hormone and norepinephrine.

Animals↗
PubMed1984

Regulation of neurohormone release in the fiddler crab, Uca pugilator: effects of gamma-aminobutyric acid, octopamine, Met-enkephalin, and beta-endorphin.

Gamma-aminobutyric acid (GABA) blocked concentration of the pigments in melanophores and erythrophores of intact crabs. GABA blocked the release of pigment concentrating hormones from the isolated eyestalk. Octopamine (OA) blocked black pigment dispersion in intact crabs, but did not affect red pigment dispersion or concentration. OA blocked the release of black pigment dispersing hormone from isolated eyestalks. Met-enkephalin, but not Leu-enkephalin, stimulated black and red pigment concentration in intact crabs. Met-enkephalin, but not Leu-enkephalin, stimulated the release of pigment concentrating hormones from isolated eyestalks. Naloxone blocked the effects of Met-enkephalin in intact crabs and on isolated eyestalks. Beta-endorphin induced black pigment dispersion in intact crabs and in isolated legs.

Animals↗
PubMed1984

A mechanism of action for the inhibition of black pigment dispersion in the fiddler crab, Uca pugilator, by naphthalene.

The polycyclic aromatic hydrocarbon, naphthalene, inhibits the circadian dispersion of epidermal black pigment in the fiddler crab, Uca pugilator, by inhibiting the release of black pigment dispersing hormone. Naphthalene caused no permanent neural damage in Uca pugilator. Naphthalene did not cause a chemically-induced phase shift in the circadian rhythm of black pigment dispersion but reduced the daytime peak of that dispersion. Black pigment concentration, which occurs at night, was not affected by exposure to naphthalene. Black pigment dispersing hormone in naphthalene-exposed crabs can be released by an injection of norepinephrine. Given the points above, and previously published data, it is concluded that naphthalene inhibits circadian black pigment dispersion in Uca pugilator by inhibiting the release of the neurotransmitter, norepinephrine.

Animals↗
PubMed1982

Roles of 5-hydroxytryptamine and dopamine as neurotransmitters eliciting release of erythrophorotropic hormones in the fiddler crab, UCA pugilator.

This article reviews the endocrinological, pharmacological and biochemical evidence ascribing neurotransmitter roles for 5-hydroxytryptamine (5-HT, serotonin) in eliciting the release of red pigment-dispersing hormone (RPDH) and for dopamine (DA) in stimulating the release of red pigment-concentrating hormone (RPCH) in the fiddler crab, Uca pugilator. 5-HT produces red pigment dispersion in intact crabs, but only indirectly. Likewise, DA evokes red pigment concentration in vivo but it has no effect on red chromatophores (erythrophores) in isolated legs. The data obtained with 5-HT and DA agonists and antagonists on red pigment translocation in vivo and in vitro, are consistent with their neurotransmitter candidacies in evoking the release of these erythrophorotropic hormones.

Animals↗
PubMed1982

Further evidence for norepinephrine as a neurotransmitter stimulating release of melanin-dispersing hormone in the fiddler crab, Uca pugilator: the changes in the melanophores of the crabs following reserpine, 6-hydroxydopamine and bretylium administration.

1. The effects on the melanophores of the fiddler crab, Uca pugilator, of the amine depletor reserpine, the catecholamine neurotoxin 6-hydroxydopamine and the noradrenergic neuron blocker bretylium were investigated. 2. The most striking effect of these drugs was that they strongly reduced the amount of melanin dispersion that normally results on transferring the crabs from a white to a black background. the drugs had no effect on pigment migration in melanophores of isolated legs. These results are in accord with the hypothesis that norepinephrine serves as a neurotransmitter stimulating release of a melanin-dispersing hormone in Uca pugilator. 3. Norepinephrine was found in the central nervous system of Uca pugilator.

Animals↗