A study of the anemia induced by hypophysectomy and that induced by combined thyroidectomy and adrenalectomy in Wistar, long-evans, and sprague-dawley rats

1956 ◽  
Vol 124 (1) ◽  
pp. 47-66 ◽  
Author(s):  
Howard A. Meineke ◽  
Roger C. Crafts
Keyword(s):  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
Long Evans

Ultrastructural Investigation of Spontaneous Pituitary Adenomas in Aging Sprague-Dawley Rats

1982 ◽  
Vol 40 ◽  
pp. 216-217
Author(s):  
D. J. McComb ◽  
J. Beri ◽  
F. Zak ◽  
K. Kovacs
Keyword(s):  
Microscopic Study ◽  
Pituitary Adenomas ◽  
Wistar Rats ◽  
Microscopic Level ◽  
Sprague Dawley ◽  
Prolactin Cells ◽  
Light Microscopic Level ◽  
Ultrastructural Investigation ◽  
Sprague Dawley Rats ◽  
Long Evans

Investigation of the spontaneous pituitary adenomas in rat have been limited mainly to light microscopic study. Furth et al. (1973) described them as chromophobic, secreting prolactin. Kovacs et al. (1977) in an ul trastructural investigation of adenomas of old female Long-Evans rats, found that they were composed of prolactin cells. Berkvens et al. (1980) using immunocytochemistry at the light microscopic level, demonstrated that some spontaneous tumors of old Wistar rats could contain GH, TSH or ACTH as well as PRL.

Oxytocin resistance in Brattleboro rat adipocytes and comparative studies on insulin or oxytocin responsiveness in normal rat adipocytes

1983 ◽  
Vol 61 (11) ◽  
pp. 1418-1425 ◽  
Author(s):  
K. Hanif ◽  
H. J. Goren ◽  
R. M. Geonzon ◽  
K. Lederis ◽  
M. D. Hollenberg
Keyword(s):  
Calcium Concentration ◽  
Maximal Response ◽  
Sprague Dawley ◽  
Assay Medium ◽  
Rat Adipocytes ◽  
Sprague Dawley Rats ◽  
Normal Rat ◽  
Increased Sensitivity ◽  
Long Evans ◽  
Treatment Use

We have evaluated factors, other than genetic, which might be related to the lack of an oxytocin-mediated insulinlike response (glucose oxidation; lipogenesis) in adipocytes from Brattleboro rats, homozygous for the diabetes insipidus trait (HoDI rats). The manoeuvres used in an attempt to restore the glucoregulatory responses to oxytocin in HoDI cells (increased glucose in the fat pad digestion medium; increased calcium concentration in the oxidation assay; estrogen treatment; use of [1-14C]glucose as substrate; inclusion of adenosine in the assay medium; vasopressin replacement therapy) uniformly failed to result in oxytocin activation of HoDI adipocytes, in contrast, the contractile responses of estrogenized HoDI rat uteri were indistinguishable from those of estrogenized normal rats. We conclude that the nonresponsiveness of the Brattleboro adipocytes to the glucoregulatory actions of oxytocin is not due to factors related to the conditions of the bioassay. On the other hand, in normal fat cells (from Sprague–Dawley and Long Evans rats), oxytocin responsiveness was augmented by a number of the manoeuvres mentioned above, most notably by the inclusion of either calcium (10 mM) or adenosine (10 μM) in the assay medium. Nonetheless, the maximum oxytocin responsiveness of adipocytes from Long Evans or Sprague–Dawley rats, under all conditions of assay, was still only a fraction (less than 20%) of the maximal response to insulin. The effect of adenosine on oxytocin action (increased sensitivity, without an effect on the maximum response) is in keeping with the previously observed effects of this nucleoside on the action of insulin; our results thus pointed to a new parallel in the action of insulin and oxytocin.

Agonistic Postures Elicited by Subdermal Shock in Sprague-Dawley and Long-Evans Rats

1975 ◽  
Vol 36 (1) ◽  
pp. 327-337 ◽  
Author(s):  
Sidney D. Duncan ◽  
D. A. Powell
Keyword(s):  
Sprague Dawley ◽  
Grid Shock ◽  
Sprague Dawley Rats ◽  
Absolute Agreement ◽  
Long Evans

Different agonistic postures were elicited by subdermal shock in Long-Evans and Sprague-Dawley rats. 0-, 1-, 2-, and 3-mA shocks were used. All postures were reliably identified by independent observers at greater than chance levels, although absolute agreement between observers was relatively poor for several postures. Long-Evans rats engaged in more aggressive postures than Sprague-Dawley animals. Agonistic postures were more frequent with 2-mA shocks in Long-Evans rats, while 3-mA shocks elicited more agonistic postures in Sprague-Dawley rats. Subdermal shock appeared to produce less variability than has been reported in previous studies where grid shock was used.

Sign in / Sign up

Export Citation Format

Share Document