Strain Differences Occurring in an Experimental Study of Punishment

1965 ◽  
Vol 16 (2) ◽  
pp. 531-536 ◽  
Author(s):  
Morton H. Kleban

Forty-three Sprague-Dawley and 43 Wistar rats were given reward training for 40 trials in a Y-maze. On the next 20 trials, control groups were continued under the same training procedure, and 50% shock trials were introduced in the training of the remaining rats. For the extinction training, the reward was shifted to the opposite arm and 50% shock was continued for the no-delay and 30-sec. delay shock groups. The most significant results were that in the 30-sec. delay groups, the delay helped the Sprague-Dawley rats reverse in a minimum number of trials, whereas the Wistar rats showed strong indications of response stereotypy. The findings with respect to the Sprague-Dawley rats supported the empirical evidence on the effectiveness of delay in overcoming response persistence and the findings on the Wistar rats supported the empirical evidence on omission in punishment. The difference in response to punishment between the two albino strains emphasizes the need for experimental study of strain factors. Experiments should be repeated with several animal strains to remedy over-generalization from single strains and to help elaborate our understanding of the interaction present between punishment and strains.

1985 ◽  
Vol 230 (2) ◽  
pp. 403-409 ◽  
Author(s):  
M D Green ◽  
C N Falany ◽  
R B Kirkpatrick ◽  
T R Tephly

Qualitative and quantitative differences of purified hepatic 3 α-hydroxysteroid UDP-glucuronosyltransferase were investigated in Wistar and Sprague-Dawley rats. Individual differences in the glucuronidation rate of androsterone and chenodeoxycholic acid were observed in hepatic microsomal fractions from Wistar but not Sprague-Dawley rats. No individual variation was observed in the glucuronidation of testosterone, p-nitrophenol or oestrone. The 3 α-hydroxysteroid UDP-glucuronosyltransferases from livers of Wistar and Sprague-Dawley rats were isolated and highly purified by using Chromatofocusing and affinity chromatography. The amount of 3 α-hydroxysteroid UDP-glucuronosyltransferase in the liver of Wistar rats exhibiting low rates for androsterone glucuronidation is about 10% or less than that found in hepatic microsomal fractions obtained from Wistar rats having high rates for androsterone glucuronidation. The apparent Km for androsterone with purified 3 α-hydroxysteroid UDP-glucuronosyltransferase from Wistar rats with high glucuronidation activity (6 microM) was not different from that observed for the enzyme purified from Sprague-Dawley animals, whereas that for the enzyme purified from Wistar rats with low glucuronidation activity was substantially higher (120 microM). Despite the differences in apparent Km values for androsterone, the apparent Km for UDP-glucuronic acid (0.3 mM) was not different in the different populations of rats.


1972 ◽  
Vol 51 (2) ◽  
pp. 619-625 ◽  
Author(s):  
D.K. Whittaker ◽  
T.R. Wilson

Restraint of different strains of rat has been shown to be capable of inducing both oral and gastric ulcers. Hooded Wistar rats were most susceptible to gastric ulcers, whereas Sprague-Dawley rats had the highest incidence of oral ulcers. The causative mechanisms probably differ and are strain dependent.


1960 ◽  
Vol 38 (3) ◽  
pp. 187-192 ◽  
Author(s):  
Joyce L. Beare ◽  
T. K. Murray ◽  
J. A. Campbell

Wistar and Sprague–Dawley rats were compared in their response to 20% rapeseed oil or corn oil in a basal diet of ground fox cubes. Apparent coefficients of digestibility were significantly lower for rapeseed oil than for corn oil in the Sprague–Dawley, but not in the Wistar rats. After 6 weeks the adrenals of Sprague–Dawley rats were larger in the animals fed rapeseed oil than in those fed corn oil, while the adrenals of Wistar rats were not influenced by the dietary oil. These strain differences explain some discrepancies appearing in the literature concerning the effects of rapeseed oil in the rat.In another experiment, Wistar and Sprague–Dawley rats deprived of vitamin A for 18 days were fed a purified basal diet with 20% rapeseed oil or corn oil and dosed with 75 or 150 I.U. of vitamin A per day. After 14 days there was no significant effect of the strain of rat or the type of dietary oil on the liver storage of vitamin A. The rate of depletion of vitamin A from the liver following a single dose of 1200 I.U. of vitamin A was also studied and indicated no significant difference attributable to the dietary oils.


2017 ◽  
Vol 45 (1) ◽  
pp. 64-75 ◽  
Author(s):  
Klaus Weber

A substantial quantity of data on Sprague-Dawley (SD) and Hannover Wistar rats strains have been published concerning their source, diet, and housing conditions, as well as the incidences of nonneoplastic lesions and neoplasms observed in different laboratories. Differences between the commonly used rat strains provided by different breeders (i.e., CD (SD) vs. Harlan Sprague-Dawley strain or Crl: WI(Han) vs. Wistar Hannover (Han)–derived strain, continued breeding by RCC Ltd., Switzerland, thereafter continued breeding by Harlan) may include, but are not limited to, body weight, incidence, and onset of major nonneoplastic lesions and neoplasms, and these can impact the development of a nonclinical safety program. Fisher 344 (F344) and SD rat strains generally have the highest tumor incidences, exceeding that in Wistar rats. Certain tumors are more commonly observed in one strain, and for some, the difference in incidence may be so significant that the tumor may even be considered characteristic for a specific strain (e.g., thymoma in Wistar and amphophilic renal adenoma in SD).


1960 ◽  
Vol 38 (1) ◽  
pp. 187-192 ◽  
Author(s):  
Joyce L. Beare ◽  
T. K. Murray ◽  
J. A. Campbell

Wistar and Sprague–Dawley rats were compared in their response to 20% rapeseed oil or corn oil in a basal diet of ground fox cubes. Apparent coefficients of digestibility were significantly lower for rapeseed oil than for corn oil in the Sprague–Dawley, but not in the Wistar rats. After 6 weeks the adrenals of Sprague–Dawley rats were larger in the animals fed rapeseed oil than in those fed corn oil, while the adrenals of Wistar rats were not influenced by the dietary oil. These strain differences explain some discrepancies appearing in the literature concerning the effects of rapeseed oil in the rat.In another experiment, Wistar and Sprague–Dawley rats deprived of vitamin A for 18 days were fed a purified basal diet with 20% rapeseed oil or corn oil and dosed with 75 or 150 I.U. of vitamin A per day. After 14 days there was no significant effect of the strain of rat or the type of dietary oil on the liver storage of vitamin A. The rate of depletion of vitamin A from the liver following a single dose of 1200 I.U. of vitamin A was also studied and indicated no significant difference attributable to the dietary oils.


Author(s):  
D. J. McComb ◽  
J. Beri ◽  
F. Zak ◽  
K. Kovacs

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.


Author(s):  
G. Ilse ◽  
K. Kovacs ◽  
N. Ryan ◽  
T. Sano ◽  
L. Stefaneanu ◽  
...  

Germfree state and food restriction have been shown to increase life span and delay tumor occurrence in rats. We report here the histologic, immunocytochemical and electron microscopic findings of adenohypophyses of aging, male Lobund-Wistar rats raised at Lobund Laboratories. In our previous study, the morphologic changes in the adenohypophyses of old rats have been extensively investigated by histology, immunocytochemistry and electron microscopy. Lactotroph adenomas were frequent in Long-Evans and Sprague-Dawley rats, whereas gonadotroph adenomas were frequent in Sprague-Dawley and Wistar rats.Male Lobund-Wistar rats were divided into four groups: 1) conventional, which were raised under normal non-germfree environment and received food ad libitum; 2) germfree-food ad libitum; 3) conventional environment-food restricted and 4) germfree-food restricted. The adenohypophyses were removed from 6-month-, 18-month- and 30-month-old rats. For light microscopy, adenohypophyses were fixed in formalin and embedded in paraffin.


1988 ◽  
Vol 255 (6) ◽  
pp. E850-E856 ◽  
Author(s):  
R. R. Almon ◽  
D. C. Dubois

This report describes changes in muscle mass of innervated and denervated pairs of muscles taken from intact and adrenalectomized 250-g male Sprague-Dawley rats provided with different diets. Diets ranged from a nutritionally complete liquid diet to starvation (water only). In the intact animals, muscles with a more tonic character (soleus) are less sensitive to starvation than are muscles with a more phasic character (extensor digitorum longus), whereas the opposite is true of denervation. In the intact animals, starvation greatly increased the amount of atrophy following denervation. In the adrenalectomized animals, starvation had no effect on the amounts of atrophy following denervation. Furthermore, adrenalectomy virtually eliminated the fiber-type differences in the amount of atrophy following denervation. In addition, a comparison between denervated muscles from intact animals and adrenalectomized animals subjected to starvation demonstrates that all denervated muscles from the adrenalectomized animals atrophy less. Finally, it was observed that although an adrenalectomized animal can tolerate 6 days of starvation, an adrenalectomized-castrated animal cannot tolerate even short periods of starvation. The difference appears to be due to low amounts of corticosterone of testicular origin.


1993 ◽  
Vol 265 (5) ◽  
pp. H1523-H1528 ◽  
Author(s):  
D. G. McCormack ◽  
N. A. Paterson

In pulmonary inflammatory processes such as pneumonia there is diminished hypoxic pulmonary vasoconstriction (HPV). We investigated whether the attenuated HPV in pneumonia is a due to excess nitric oxide (NO) release. Sprague-Dawley rats were anesthetized, and a slurry (0.06 ml) of infected agar beads (containing 6 x 10(5) Pseudomonas aeruginosa organisms) or control (sterile) beads was then injected into a distal bronchus through a tracheotomy. After the establishment of a chronic P. aeruginosa pneumonia (7-10 days later) animals were instrumented for hemodynamic monitoring, and the response to exposure to hypoxic gas (fraction of inspired O2 = 0.08) was recorded before and after the administration of NG-monomethyl-L-arginine (L-NMMA; 50 mg/kg), an inhibitor of NO synthesis. The hypoxic pressor response, as assessed by the absolute increase in pulmonary arterial pressure (PAP) and total pulmonary resistance (TPR), was reduced in infected animals compared with control animals. The change in PAP and TPR was 8.5 +/- 0.7 and 0.053 +/- 0.007, respectively, in control animals compared with 5.9 +/- 0.5 and 0.041 +/- 0.011 in infected animals. After L-NMMA the increase in PAP and TPR during hypoxia was greater in both control and infected animals. However, treatment with L-NMMA did not affect the difference between control and infected animals. We conclude that excess release of NO does not account for the attenuated hypoxic pressor response in pneumonia.


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