Estrogen receptor-α immunoreactive neurons in the brainstem and spinal cord of the female rhesus monkey: Species-specific characteristics

The results indicate that ER-α IR neurons in the primate brainstem and spinal cord are concentrated mainly in regions involved in sensory and autonomic processing. Compared with rodent species, the regional distribution of ER-α IR neurons is less widespread, and ER-α IR neurons in regions such as the spinal dorsal horn and caudal spinal trigeminal nucleus appear to be less abundant. These distinctions suggest a modest role of ER-α in estrogen-mediated actions on primate brainstem and spinal systems. These differences may contribute to variations in behavioral effects of estrogen between primate and rodent species.