Vitamin D deficiency in human subjects is associated with hypertension, metabolic syndrome and related risk factors of cardiovascular diseases. Serum 25-hydroxyvitamin D levels correlate inversely with adiposity in obese and lean individuals. Bioactive vitamin D, or calcitriol, exerts anti-inflammatory effects on adipocytes, preadipocytes and macrophages in vitro. We tested the hypothesis that vitamin D deficiency alters the phenotype of perivascular adipose tissue (PVAT) leading to impaired function in resistance artery. To examine the effects of vitamin D and PVAT on vascular reactivity, myograph experiments were performed on arteries, with or without intact PVAT, from mice maintained on vitamin D-deficient, vitamin D-sufficient or vitamin D-supplemented diet. Systolic blood pressure was significantly increased in mice on vitamin D-deficient diet. Importantly, vitamin D deficiency enhanced angiotensin II-induced vasoconstriction and impaired the normal ability of PVAT to suppress contractile responses of the underlying mesenteric resistance artery to angiotensin II and serotonin. Furthermore, vitamin D deficiency caused upregulation of the mRNA expression of tumor necrosis factor-α, hypoxia-inducible factor-1α and its downstream target lysyl oxidase in mesenteric PVAT. Incubation of mesenteric arteries under hypoxic conditions impaired the anti-contractile effects of intact PVAT on those arteries from mice on vitamin D-sufficient diet. Vitamin D supplementation protected arteries against hypoxia-induced impairment of PVAT function. The protective effects of vitamin D against vascular dysfunction, hypertension and cardiovascular diseases may be mediated, at least in part, through regulation of inflammatory and hypoxia signaling pathways in PVAT.

PROBLEMThere are two contradictory viewpoints regarding the type of familial atniosphere which is most conducive t o achievement motivation, namely the free permissive type of environment and the more authoritarian or restrictive type of home setting. Proponents of the former view cite such animal studies as Christie's'') and Thompson and Melzack's ( 9 ) which shotved retardation in various psychological traits as a result of early restriction. Psychoanalysts such as C r e e n a~r e '~) have argued that the frustrations engendered by parental restraints may impair intellectual efficiency because of an increase in sado-masochism and resulting anxiety in the child. On the other side of the issue stand P e a r~o n '~) and Liss(b) n h o look upon the acquisition of kno:\ledge and society's symbols as a process of sublimation. They feel that if a child is allowed too much freedom he ]Till remain a t the mercy of the pleasure principle.Perhaps one source of confusion in this issue has been the tendency t o use such words as "democratic" t o stand !or the "good" parent, and "authoritarian" to stand for the "bad" parent, while the actual operational definitions of these nords vary from investigator t o investigator. It is questionable ~3 hether any parent can completely escape the role of an authoritarian during the formative years of a child's life. I n this respect Lewin(4) has identified t m o different kinds of restrictive parental attitudes, one of which sets certain limits upon the child's behavior .vlhile a t the same time encouraging him t o engage in acceptable activities. The other, houever, issues "blanket warnings" leaving the child insecure and afraid to engage in any new behavior. The importance of parental intervention is also contained in the book of McClelland ( 6 ) and Winterbottom (I1) who have emphasized the importance of parental demands upon achievement motivation. Such demands for certain standards of excellence in the child would seem to imply something different than mere passive permissiveness. It is therefore the thesis of this paper that the parents of high academic achievers \till actually be less permissive and accepting in the treatment of their children than the parents of low academic achievers. SUBJECTSParents of Gifted Students. One group consisted of the mothers of forty junior high school students of gifted intelligence (I& of 130 or more on the Stanford-Binet).Twenty of these students (ten girls and ten boys) had maintained a uniform grade point average of "A" o~e r a, previous two-year period and they were identified as high achievers. A group of low achievers (ten girls and ten boys) were matched to these students t o within five I& points on the Stanford-Binet, and t o aithin six months in age. These low achieving students had maintained only a "€3 minus" or lower grade point average throughout the previous two-year 9eriod of their school history. An attempt VI as also made to equate the groups for socio-economic status by matching high and low achievers on the basis of their fat...

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