Although the neuroanatomical distribution of catecholaminergic (CA) neurons has been well documented across all vertebrate classes, few studies have examined CA connectivity to physiologically and anatomically identified neural circuitry that controls behavior. The goal of this study was to characterize CA distribution in the brain and inner ear of the plainfin midshipman fish (Porichthys notat...

Gbx2 is a homeobox-containing transcription factor that is related to unplugged in Drosophila. In mice, Gbx2 and Otx2 negatively regulate each other to establish the mid-hindbrain boundary in the neural tube. Here, we show that Gbx2 is required for the development of the mouse inner ear. Absence of the endolymphatic duct and swelling of the membranous labyrinth are common features in Gbx2-/- in...

The radial count method of Emery and Mithal was applied to the lungs of 37 infants of gestational age 19-42 weeks. The method could be used satisfactorily to evaluate airspace-containing lungs, whether alveolated or non-alveolated (saccule-containing). There was a progressive increase in complexity of terminal lung units throughout gestation, and a smooth transition was effected at 1 month of a...

Neural responses to sensory stimuli often differ between sexes, vary seasonally, and can be regulated by endocrine activity, but the ecological and physiological mechanisms driving such patterns are not well understood. The current study examined how auditory function in the round goby (Neogobius melanostomus), a vocal teleost, co-varied with sex, reproductive condition and female plasma 17β-es...

The quantitative analysis of fluorescence in frozen sections of rat inner ears exposed to Texas Red conjugated gentamicin revealed distinct gradients of gentamicin fluorescence. At 500 µg/ml gentamicin fluorescence occurred in inner and outer hair cells, the interdental cell region, the spiral limbus below the interdental cells, the nerve fiber bundle in the spiral lamina, the inner sulcus cell...

Two methods used for the electron microscopic detection of glycoproteins were applied to a variety of cell types in the rat; one involved successive treatment of sections with periodic acid, chromic acid, and silver methenamine; and the other, a brief treatment with a chromic acid-phosphotungstic acid mixture. The results obtained with the two methods were identical and, whenever the comparison...

Acoustic sensitivity of the human vestibular system has long been established and can be demonstrated by means of the cervical vestibular evoked myogenic potential (cVEMPs). The objective of this cross-sectional study is to investigate the possibility that the acoustic sensitivity of the saccule improves stapedial muscle reflex threshold. Twenty healthy persons and twenty-five patients as havin...

In goldfish and other otophysans, the Weberian ossicles mechanically link the saccule of the inner ear to the anterior swimbladder chamber (ASB). These structures are correlated with enhanced sound-pressure sensitivity and greater sensitivity at high frequencies (600-2000 Hz). However, surprisingly little is known about the potential impact of the ASB on other otolithic organs and about how aud...

Efforts to identify the specific components of the mammalian inner ear have been hampered by the small number of neuroepithelial cells and the variety of supporting cells. To circumvent these difficulties, we used a PCR-based subtractive method on cDNA from 2-day-old mouse cochlea. A cDNA encoding a predicted 2910-amino acid protein related to mucin has been isolated. Several lines of evidence ...