New cells, including neurons, arise in several brain regions during puberty in rats. Sex differences in pubertal addition of cells coincide with adult sexual dimorphisms: for each region, the sex that gains more cells during puberty has a larger volume in adulthood. Removing gonadal hormones before puberty eliminates these sex differences, indicating that gonadal steroids direct the addition of new cells during puberty to maintain and accentuate sexual dimorphisms in the adult brain.

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Neuron-to-glia, glia-to-neuron, and glia-to-glia communication are implicated in the modulation of neuronal activity and synaptic transmission relevant to reproduction. Glial cells play an important role in neuroendocrine regulation and participate in the sexual differentiation of neuronal connectivity of brain regions involved in the control of reproductive neuroendocrine output. During puberty, modifications in the morphology and chemistry of astrocytes and tanycytes in the hypothalamus and median eminence influence the maturation of the neuronal circuits controlling the secretion of GnRH. During adult reproductive life, the glial cells participate in the transient remodeling of neuronal connectivity in the preoptic area, the arcuate nucleus, the median eminence, and other brain regions involved in the control of reproduction. Gonadal hormones regulate glial plasticity by direct and indirect effects and regulate various other endocrine signals, local soluble factors and adhesion molecules that also affect glial function and glia-to-neuron communication. The glial cells, therefore, are central to the coordination of endocrine and local inputs that bring about neural plasticity and adapt reproductive capacity to homeostatic signals.

Androgen exposure during development and adulthood promotes cell‐to‐cell communication, modulates the size of specific brain nuclei, and influences hormone‐dependent behavioral and neuroendocrine functions. Androgen action involves the activation of androgen receptors (AR). To elucidate the mechanisms involved in AR‐mediated effects on forebrain development, double‐label fluorescent immunohistochemistry and confocal microscopy were employed to identify the cellular phenotype of AR‐immunoreactive (AR+) cells in the developing (embryonic day 20, postnatal days 0, 4, 10) and adult male rat forebrain. Sections were doubly labeled with antibodies directed against AR and one of the following: neurons (immature, nestin; mature, NeuN) or astrocytes [immature, vimentin; mature, glial fibrillary acidic protein (GFAP)] or mature oligodendrocytes (mGalC). In all brain regions examined, by far the majority of AR+ cells were neurons. In addition, small subsets of AR+ cells were identified as mature astrocytes (GFAP+) but only in specific brain regions at specific ages. AR+/GFAP+ cells were observed in the cerebral cortex but only in postnatal day 10 rats and in the arcuate nucleus of the hypothalamus but only in adult rats. Immature neurons, immature astrocytes, and oligodendrocytes were not AR+ at any age, in any region. Thus, both neurons and astrocytes in the male rat forebrain contain ARs, suggesting that androgens, via ARs, may exert effects on both cell types in an age‐ and region‐dependent manner. J. Comp. Neurol. 492:456–468, 2005. © 2005 Wiley‐Liss, Inc.

Patients with better antidepressant adherence and adherence/persistence demonstrated better HbA1c control, with lower all-cause total and medical costs. Adherence, persistence, or adherence/persistence to antidepressants was associated with improved adherence to oral diabetes medications.