Quantitative subunit hybridization of drosophilaα-Glycerophosphate dehydrogenase

1978 ◽  
Vol 12 (2) ◽  
pp. 173-182 ◽  
Author(s):  
G. E. Collier ◽  
R. J. MacIntyre
Author(s):  
E. A. Elfont ◽  
R. B. Tobin ◽  
D. G. Colton ◽  
M. A. Mehlman

Summary5,-5'-diphenyl-2-thiohydantoin (DPTH) is an effective inhibitor of thyroxine (T4) stimulation of α-glycerophosphate dehydrogenase in rat liver mitochondria. Because this finding indicated a possible tool for future study of the mode of action of thyroxine, the ultrastructural and biochemical effects of DPTH and/or thyroxine on rat liver mere investigated.Rats were fed either standard or DPTH (0.06%) diet for 30 days before T4 (250 ug/kg/day) was injected. Injection of T4 occurred daily for 10 days prior to sacrifice. After removal of the liver and kidneys, part of the tissue was frozen at -50°C for later biocheailcal analyses, while the rest was prefixed in buffered 3.5X glutaraldehyde (390 mOs) and post-fixed in buffered 1Z OsO4 (376 mOs). Tissues were embedded in Araldlte 502 and the sections examined in a Zeiss EM 9S.Hepatocytes from hyperthyroid rats (Fig. 2) demonstrated enlarged and more numerous mitochondria than those of controls (Fig. 1). Glycogen was almost totally absent from the cytoplasm of the T4-treated rats.


1978 ◽  
Vol 12 (2) ◽  
pp. 183-188 ◽  
Author(s):  
G. E. Collier ◽  
K. Moffat ◽  
R. J. MacIntyre

2002 ◽  
Vol 87 (2) ◽  
pp. 147-155 ◽  
Author(s):  
Francisco B. Barbosa ◽  
Kirsten Capito ◽  
Hans Kofod ◽  
Peter Thams

Pancreatic islets were isolated from rats that had been nursed by dams fed with a control or an 8·7 % protein diet during the first 12 d of the lactation period. Glucose-induced insulin secretion from islets in the 8·7 % protein group was reduced 50 %. The islet insulin and DNA content were similar, whereas the pancreatic insulin content was reduced by 30 % in the rats fed 8·7 % protein. In order to elucidate the mechanism responsible for the attenuation of insulin secretion, measurements were performed of the activity of several islet enzymes that had previously been supposed to be involved in the coupling of glucose stimulation to insulin secretion. Islet glucose oxidation was unaffected, but glucose-stimulated hydrolysis of phosphatidylinositol was reduced by one-third in the islets of rats fed 8·7 % protein. The activity of mitochondrial glycerophosphate dehydrogenase was similar in islets of rats fed the 8·7 % protein diet and those fed the control diet. The activity of Ca-independent phospholipase A2was increased fourfold in the islets of rats fed 8·7 % protein. It is concluded that impairment of glucose-induced insulin secretion in rats fed a low-protein diet may be caused by attenuation of islet phosphatidylinositol hydrolysis, and it is tentatively suggested that the increased activity of Ca-independent phospholipase A2in islets of rats fed a low-protein diet may participate in the stimulation of apoptosis.


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