Groups of pregnant rats were injected with two successive daily doses of 3H-thymidine from gestational days 12 and 13 (E12 + 13) until the day before birth (E21 + 22). In radiographs from adult progeny of these rats the proportion of neurons generated on specific days was determined in the major nuclei of the upper medulla, with the exception of the vestibular and auditory nuclei. The neurons o...

Neurons in the medullary reticular formation (MRF) of the rat receive a vast array of urogenital inputs. Using select acute and chronic spinal cord lesions to identify the location of the ascending neural circuitries providing either direct or indirect inputs to MRF from the penis, our previous studies demonstrated that the dorsal columns and dorsal half of the lateral funiculus convey low- and...

Despite the fact that a number of individuals present with a hypersensitive gag reflex, research in this area has been limited to clinical applications. An animal model that describes the neurologic underpinnings of the gag reflex has not been reported. Thus, the objective of the current study was to localize activated neurons in the rat medulla and to investigate their neurochemistry following...

We tested the hypothesis that application of the subunit B of cholera toxin (CTB) to the airway mucosa would produce labeling of neuronal somata and sensory fibers in the medulla oblongata. Using (125)I-CTB as a tracer, we demonstrated first that CTB is transported across the tracheal epithelium, but once in the airway wall, it remains confined to the subepithelial space and lamina propria. Des...

By definition central respiratory chemoreceptors (CRCs) are cells that are sensitive to changes in brain PCO(2) or pH and contribute to the stimulation of breathing elicited by hypercapnia or metabolic acidosis. CO(2) most likely works by lowering pH. The pertinent proton receptors have not been identified and may be ion channels. CRCs are probably neurons but may also include acid-sensitive gl...

Sexually dimorphic behaviors develop under the influence of sex steroids, which induce reversible changes in the underlying neural network of the brain. However, little is known about the proteins that mediate these activational effects of sex steroids. Here, we used a proteomics approach for large-scale identification of proteins involved in the development of a sexually dimorphic behavior, th...

Larval lampreys respond to skin illumination with a delayed burst of swimming in an attempt to escape the light. The photoresponse, which is independent of the lateral eyes and pineal organs, is most readily elicited by light shone on the tail. Behavioral studies in larval lampreys demonstrate that photosensory afferents innervating the tail are carried by a trunk lateral line nerve supplying r...

There are some observations which suggest the possibility of existence of cholinergic mediation in central integration of vomiting. Pilocarpine, a parasympathomimetic agent produces vomiting on intraventricular administration (1). Almost all the antiemetic agents possess antiacetylcholine activity to a varying degree. Moreover, central integration of vomiting occurs at the medullary level and i...

  We report an unusual case of a young male with cerebellar hemangioblastoma treated previously for medullary carcinoma of thyroid, whose PET/CT scans revealed a constellation of findings that suggested the rare Von Hippel Lindau syndrome. The diagnosis was clinched by confirming the findings on whole body contrast enhanced computed tomography (CECT) and contrast enha...

Immune activation results in adaptive neuroendocrine responses, including activation of the hypothalamic-pituitary-adrenal axis, which are dependent on the integrity of medullary catecholaminergic (CA) systems. In contrast, although specific roles of pontine, midbrain, and hypothalamic CA systems in neuroendocrine function have been described, the functional roles of these CA systems in modulat...