✦ LIBER ✦

The effect of cyclic AMP and cytochalasin B on tissue cultured melanophores of Xenopus laevis

✍ Scribed by Timothy A. Lyerla; Ronald R. Novales

Publisher: John Wiley and Sons
Year: 1972
Tongue: English
Weight: 723 KB
Volume: 80
Category: Article
ISSN: 0021-9541
DOI: 10.1002/jcp.1040800211

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

The effects of cytochalasin B or low concentrations of adenosine 3′,5′‐monophosphate (cyclic AMP) were tested on melanophores in hanging drop preparations of neural fold explants from Xenopus laevis embryos in Barths' solution. After one week in culture, the melanophores were punctate in this medium. Cyclic AMP at 5 mM consistently caused reversible morphological transformation of these cells to the stellate state, whether they were situated within an epithelial outgrowth or isolated on the surface of the coverglass. Only the isolated melanophores consistently responded to 1 mM cyclic AMP. Cytochalasin B at 1–10 μg/ml caused aggregation of melanin granules in stellate cells, but left long, narrow cell branches containing some melanosomes. Its effect was at least partially reversible and appeared to be dose dependent. At 1% concentration, dimethyl sulfoxide caused melanin dispersion.

📜 SIMILAR VOLUMES

The effect of cytochalasin B on pigment

The effect of cytochalasin B on pigment dispersion and aggregation in perfused Xenopus laevis tailfin melanophores

✍ Marilyn Fisher; Timothy A. Lyerla 📂 Article 📅 1974 🏛 John Wiley and Sons 🌐 English ⚖ 788 KB

## Abstract A perfusion technique is described for the study of melanosome response in ventral tailfin melanophores of __Xenopus laevis__ tadpoles. The melanosomes remain aggregated (punctate melanophores) in Ringer's. Theophylline (15 mM) and caffeine (30 mM) cause a reversible dispersion (stellat

The effect of insulin on basal and hormo

The effect of insulin on basal and hormone-induced elevations of cyclic AMP content in cultured human fibroblasts

✍ Judith W. Rosenthal; Samuel Goldstein 📂 Article 📅 1975 🏛 John Wiley and Sons 🌐 English ⚖ 587 KB

## Abstract Studies were carried out on confluent cultures of human fibroblasts to explore the effect of insulin on basal and hormone‐induced elevations of intracellular cyclic AMP content during short‐term incubations in serum‐free medium. Insulin tended to decrease basal levels of cyclic AMP but

The effect of histamine on the growth of

The effect of histamine on the growth of cultured fibroblasts isolated from normal and keloid tissue

✍ James D. Russell; Shirley B. Russell; Kathryn M. Trupin 📂 Article 📅 1977 🏛 John Wiley and Sons 🌐 English ⚖ 483 KB 👁 1 views

## Abstract Cultured fibroblasts derived from human keloid tissue are presented as a possible model system for studying the genetic regulation of cell growth. Histamine is shown to have a marked effect on the growth of cultured fibroblasts. A small increase in growth rate is seen during the log pha

Dual effects of glucagon and cyclic amp

Dual effects of glucagon and cyclic amp on dna synthesis in cultured rat hepatocytes: Stimulatory regulation in early G1 and inhibition shortly before the s phase entry

✍ G. Hege Thoresen; Tor-Erik Sand; Magne Refsnes; Olav F. Dajani; Tormod K. Guren; 📂 Article 📅 1990 🏛 John Wiley and Sons 🌐 English ⚖ 964 KB

Blindern, N-0316 0 t h 3 , Norway Although several lines of evidence implicate cyclic AMP in the humoral control of liver growth, its precise role is still not clear. To explore further the role of cyclic AMP in hepatocyte proliferation, we have examined the effects of glucagon and other cyclic AMP-

The effect of polyoma virus, serum facto

The effect of polyoma virus, serum factors, and dibutyryl cyclic AMP on dihydrofolate reductase synthesis, and the entry of quiescent cells into S phase

✍ Thomas M. Gudewicz; Vera B. Morhenn; Rodney E. Kellems 📂 Article 📅 1981 🏛 John Wiley and Sons 🌐 English ⚖ 767 KB

## Abstract Three procedures were used to induce dihydrofolate reductase synthesis in quiescent cultures of methotrexate resistant mouse fibroblasts: (1) lytic infection with polyoma virus, (2) growth stimulation by replating cells at lower density in fresh cell culture medium, and (3) the addition

Combined effect of adenosine 3′, 5′-cycl

Combined effect of adenosine 3′, 5′-cyclic monophosphate stimulating agents, vitamin e succinate, and heat on the survival of murine b-16 melanoma cells in culture

✍ Satya N. Sahu; Kedar N. Prasad 📂 Article 📅 1988 🏛 John Wiley and Sons 🌐 English ⚖ 494 KB 👁 2 views