Reference

Noradrenaline induced secretion of nonelectrolytes through frog skin

Noradrenaline induced secretion of nonelectrolytes through frog skin. Svelto, M.; Perrini, M. C. R.; Lippe, C. (Inst. Gen. Physiol., Univ. Bari, Bari, Italy). J. Membr. Biol., 36(1), 1-11 (English) 1977. CODEN: JMBBBO. DOCUMENT TYPE: Journal CA Section: 2 (Hormone Pharmacology) Section cross-reference(s): 12 Addn. of noradrenaline (I) [51-41-2] (4 .times. 10-5M) to the inner bathing fluid in the skin of the frog Rana esculenta resulted in increased unidirectional fluxes of urea [57-13-6], thiourea [62-56-6], N-methylthiourea [598-52-7], N,N-dimethylthiourea [6972-05-0], and mannitol [69-65-8]. Fluxes towards the external medium (.vphi.0) showed much greater increases than those moving in the opposite direction (.vphi.i). The effect of I on .vphi.0 was higher for urea and thiourea than mannitol, whereas its effect on .vphi.0 thiourea derivs. was related to lipid soly. This phenomenon did not occur for .vphi.i of the same mols. P-trifluoromethoxycarboxycyandidephenylhydrazone (10-6M) pretreatment strongly inhibited the I effect on .vphi.0. In skin pretreated with colchicine (2 .times. 10-5M), both urea fluxes were increased to the same extent by I. I apparently exerts 2 sep. effects: a change in permeability in both directions; a secretion of nonelectrolytes towards the external fluid.

Phenylthiourea enhances copper cytotoxicity in cell cultures: its mode of action

Phenylthiourea enhances copper cytotoxicity in cell cultures: its mode of action. Masuda, Akira; Eguchi, Goro (Fac. Sci., Nagoya Univ., Nagoya 464, Japan). Cell Struct. Funct., 9(1), 25-35 (English) 1984. CODEN: CSFUDY. ISSN: 0386-7196. DOCUMENT TYPE: Journal CA Section: 4 (Toxicology) Phenylthiourea (PTU) [103-85-5] markedly enhanced the cytotoxic effects of CuCl2 on chick embryonic pigment epithelial cell (PECs) cultured in vitro. This newly discovered effect of PTU and its analogs in relation to the toxic effects of Cu ion was investigated. Most PECs maintained in medium contg. 0.5 mM PTU were lysed within 4 h after the addn. of 0.1 mM CuCl2. CuCl2 alone had no effect on PECs. The effect of PTU was not specific to PECs. All the cell lines (KB, N-18, N-115 and B-16) tested responded to exogenous Cu in the presence of PTU as did PECs. Analogs of PTU had similar effects on PECs in the presence of Cu ion. a-Naphthylurea (I) [6950-84-1] had a greater effect than PTU. N-Methylthiourea [598-52-7] and thiourea [62-56-6] had less effect than PTU. PTU did not affect the cytolysis induced by the addn. of the divalent cations Mn, Co and Zn. The 64Cu uptake by PECs was 6-fold higher in the presence than in the absence of PTU. The relation between this cytotoxic-enhancing effect and other biol. activities of PTU are discussed.