The effect of dehydration on the neurohypophyseal blood flow in rats with hereditary diabetes insipidus

Summary Neurohypophyseal blood flow increases in water-deprived rats. This increase is independent of vasopressin release, since it occurs even in rats with hereditary defect of hypothalamic vasopressin synthesis.Acknowledgment. The technical assistance of D. Vilimovská is acknowledged.     

Model of the effect of 4-aminopyridine at the level of potassium channels of the giant axon of the squid, Logigo forbesi L.]

Most of the effects of 4-aminopyridine on the potassium conductance of the giant axon of the Squid can be explained in terms of a simple model based on the physicochemical properties of the molecule and what is known about the structure of the potassium "channels".     

An electrophoretic investigation of the binding of 3-14C coumarin to rat serum proteins

Summary The binding of coumarin to serum proteins of the rat has been demonstrated. Of the total bound coumarin (37% of injected dose), 36% was bound to the slow and fast ₁ globulins, 11% to the post albumins, 10% to globulin and 9% to albumin.     

The metabolism of the male antifertility agent 1-amino-3-chloropropan-2-ol in the rat

Summary The male antifertility agent 1-amino-3-chloropropan-2-ol (ACP,I) has been shown to be metabolized to-chlorohydrin (III) and metabolites of-chlorohydrin. This accounts for the similar antifertility and renal toxicity effects of both compounds.     

A cannabinoid with cardiovascular activity but no overt behavioral effects

Summary Abnormal-⁸-tetrahydrocannabidiol (ABN-⁸-THC) failed to elicit central nervous system and cardiovascular effects in laboratory animals. Abnormal-cannabidiol (ABN-CBD) was also devoid of overt behavioral effects but produced marked hypotension with only slight bradycardia in anesthesized dogs.Acknowledgment. This work was supported by NIDA (grant No. DA-00574-01 and DA-00490) and Virginia Heart Society (grant No. RR-05697)     

A tissue-selective prostaglandin E2 analog with potent antifertility effects

Summary N-methanesulfonyl 16-phenoxy--tetranor PGE₂ is a prostaglandin analog which is markedly more tissue selective than PGE₂. This compound is 10–30 times more potent than PGE₂ in animal models which are considered relevant to antifertility effects in humans. In pharmacological tests which are believed to be predictive for side effects in humans, the compound has potency either equal to or less than that of PGE₂.     

Transposable genetic elements as agents of gene instability and chromosomal rearrangements.

Transposable genetic elements in prokaryotes and eukaryotes, when inserted at a given locus, can control expression of the locus and cause large scale rearrangements of adjacent DNA sequences. Striking similarities in genetic behaviour between the two groups of elements have led to the proposal of a molecular model of eukaryotic controlling elements, and to suggestions about the part such elements may play in evolution and differentiation.     

Determinant selection is a macrophage dependent immune response gene function

Immune response (Ir) genes are linked to the species histocompatibility complex and define as yet uncharacterised phenotypic products which control the immune response to thymus dependent antigens. Antibody formation and antigen induced T lymphocyte proliferation are two examples of immune phenomena which, in vivo and in vitro, operate under Ir gene influence. To clarify their mechanism of action and cellular location, we have examined the contribution of antigen structure (amino acid sequence and conformation to Ir gene control of antigen recognition by T lymphocytes) as well as to the critical role played by the antigen presenting macrophage in expression of that control. We report that immune response gene control of antigen recognition operates at least in part at the level of the macrophage.