Human growth hormone may differentially influence the grasp reflex in human neonates on the basis of genetically predetermined neural pattern of brain organization in utero.
The relations of the grasp-reflex strengths from right (R) and left (L) hands to human growth hormone (hGH) levels were studied in human neonates within the first day after birth. In right-handed (RH) males without familial sinistrality (-FS), grasp reflex from right and left hands directly correlated with hGH. In RH, -FS females, grasp reflex from right and left hands inversely correlated with hGH. In -FS, LH males, grasp reflex from right and left inversely correlated with hGH (no significant correlations in LH, -FS females). The R-L grasp reflex decreased linearly with hGH, only in RH, -FS males. These results indicated that hGH may affect cerebral development according to genetically predetermined neural patterns in utero.
Tan
U
U
Department of Physiology, Medical Faculty, Ataturk University, Erzurum, Turkey.
D001921:Brain / Q000196:embryology* / Q000502:physiology; D005314:Embryonic and Fetal Development / Q000502:physiology*; D005260:Female; D007839:Functional Laterality / Q000235:genetics; D013006:Growth Hormone / Q000097:blood / Q000235:genetics / Q000502:physiology*; D006225:Hand / Q000502:physiology*; D006801:Humans; D007231:Infant, Newborn / Q000502:physiology*; D008297:Male; D009119:Muscle Contraction / Q000235:genetics / Q000502:physiology; D012018:Reflex / Q000235:genetics / Q000502:physiology*; D012737:Sex Factors
D013006:Growth Hormone