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J B Whitney

Publications and source records attributed to J B Whitney.

41 records · Page 3Linked to original sources

Effects of anterior hypothalamic lesions on the sexual behavior of prenatally-stressed male rats.

Sprague-Dawley females were exposed to the stress of heat, restraint and bright lights during the third trimester of gestation. Virtually all male offspring tested for masculine sexual behavior as adults ejaculated and copulated with lure females. Also prenatally-stressed males exhibited two to three times as many lordotic responses as did males from nonstressed mothers. Because animals were crossfostered, an in utero action of prenatal stress is supported. Anterior hypothalamic (AHA) lesions significantly reduced the number of lordotic responses observed in prenatally-stressed male rats compared to those observed in prenatally-stressed males bearing sham lesions of the AHA. The possibility is presented that prenatal stress may influence the developing male brain.

Animals↗

Differential control of the synthesis of two hemoglobin beta chains in normal mice.

A fetal-to-adult switch in the proportion of the mouse minor hemoglobin is described. Although mice have no fetal hemoglobin per se, the timing of this switch in the mouse suggests that the mechanism of its control may directly parallel that of the human switch from fetal to adult hemoglobin expression. The mouse minor hemoglobin is expressed only in strains with the "diffuse" allele for the beta chain complex locus. Fetal liver cells of these mice synthesize a much greater proportion of the betaminor globin chain that do adult hematopoietic cells. Consequently, circulating fetal erythrocytes carry a high level of the minor hemoglobin containing it. By the time of birth, a lowered proportion of betaminor is synthesized in the liver. This low proportion continues to be expressed during early erythroid maturation in the adult. The fetal-to-adult switch is the first indication that in normal mice, the two beta chain loci can be expressed noncoordinately. The similarity between the patterns of the decline of the minor hemoglobin in mice and of the disappearance of fetal hemoglobin in humans suggests that the minor hemoglobin in the "diffuse" mouse may function to some degree as a fetal hemoglobin in the period between the disappearance of the embryonic hemoglobins and the time of birth.

Animals↗

Effects of prepartal stress on postpartal nursing behavior, litter development and adult sexual behavior.

Sprague-Dawley rats were exposed to the stress of restraint, heat and bright lights three times daily from Days 14 to 22 of gestation. Because prepartal stress did not markedly disturb the mother's retrieving and crouching behavior, disturbances in postpartal nursing behavior do not seem to account for the abnormal sexual behavior of male offspring as adults. The most significant finding was that litter weights were reduced, not only at birth, but for 3 weeks thereafter, suggesting that prepartal stress not only altered the pups in utero but also affected postpartal milk synthesis. The possibility emerges that prepartal stress may alter adult sexual behavior in males by modifications in fetal and/or maternal pituitary glands.

Animals↗

Transposable elements controlling genetic instabilities in mammals.

It is proposed that the instabilities in gene action of some alleles at certain loci in the mouse (e.g., a, c, H-2 Mi, p, pe, T, Va, W), which do not seem to conform to traditional hypotheses of gene action, are better interpretable in the light of modern studies of transposable DNA elements (insertion sequences and transposons of prokaryotic organisms; controlling elements of maize; transposable controlling elements of Drosophila). Some phenotypic evidence in the mouse in support of this hypothesis is presented for the a, Mi, p, and W loci, which affect pigmentation.

Animals↗