Figure 1.
CRH mRNA expression is reduced in PVN of rats handled recurrently (from P2–P8) but not in those handled once. A, Bright-field and dark-field photomicrographs of coronal sections at the level of the PVN that were subjected to in situ hybridization for CRH mRNA and then emulsed. B, Quantitative analysis of CRH signal over PVN. Basal levels of CRH expression were reduced by 52% in P9 rats handled daily on P2–P8 compared with those of pups left undisturbed (Und). Handling once was insufficient to induce changes in gene expression: CRH mRNA levels in PVN of P9 rats handled once, either on P5 or on P8, did not differ from those of undisturbed controls (p = 0.64 and 0.99, respectively). H(P2–P8), Handled daily from P2 to P8; H(P5), handled once on P5; H(P8), handled once on P8. Vertical line labeled “3rd” indicates the third ventricle. Scale bars, 500 μm. *p < 0.001, values are significantly different from undisturbed. n = 6–7 brains per group.
