Segregation phenomena of 66 offspring from matings of the black rat (Rattus rattus) having 1, 2 and 3 supernumeraries are analysed cytogenetically. The occurrence of a large number of the supernumeraries in the offspring is informative of nondisjunction in meiosis of the parents.
The capillary arrangement of the endometrium is studied in the rabbit by means of injection replica scanning electron microscopy. On the 7th day of pseudopregnancy, the vascularity of the endometrium is similar to that of normal pregnancy. In the 9th-day pseudopregnancy, the vascularity shows a similar change to that of the 7th-day sample, except for many occluded or torn-off capillaries, which are observed rather frequently in the subepithelial plexus. They have an important implication to the change of vascularity during pseudopregnancy.
Human platelet insulin receptors were investigated in 21 young healthy Japanese subjects. Insulin specific binding was evident in the platelets, and binding sites had two constant orders of affinity. The high affinity site (Kaff=4.4×1010M-1) had a low capacity (55 sites/cells) while the lower affinity site (Kaff=2.9× 107M-1) had a higher capacity (1400/cells). Binding of 125I-insulin to platelets was maximal at 4°C, and at pH 7.4-8.0. These results indicate that human platelet insulin receptors have characteristics similar to those seen in lymphocyte insulin receptors. This evidence suggests that further investigation of the action of insulin on platelets is warranted.