Characterization of the rhesus monkey superior olivary complex by calcium binding proteins and synaptophysin

Abstract

This study was performed in order to characterize the main nuclei of the rhesus monkey superior olivary complex by means of antibodies against the calcium binding proteins parvalbumin, calbindin and calretinin and the synaptic vesicle protein synaptophysin. These markers revealed the neuronal morphology and organization of nuclei located within the rhesus monkey superior olivary complex. The architectural details included the distribution of axonal terminals on neurons. The medial superior olivary nucleus was present as a column of neurons. No clear segregation of calretinin-positive terminals was noticed on the medial and lateral dendritic fields of these neurons.The lateral superior olivary nucleus was characterized by a distinct nuclear shape. Calretinin-, parvalbumin-or calbindin-positive terminals contacted somata and dendrites. The medial nucleus of trapezoid body could be clearly differentiated as a distinct region in the rhesus monkey superior olivary complex. Somata of that nucleus showed calbindin-and parvalbumin-labelling whereas somatic calyces of Held were reavealed by calretinin and synaptophysin labelling. The results are discussed with respect to the processing of acoustic information in primate species and their ability to hear high and low frequencies, which is reflected by anatomical correlates.

Developmental Profiles of the Intrinsic Properties and Synaptic Function of Auditory Neurons in Preterm and Term Baboon Neonates

“…Previous immunohistochemical study in the SOC of adult rhesus monkey demonstrated that the MNTB soma was encircled by a dense assembly of synaptophysin-positive terminals, which corresponded to the calyces of Held (Bazwinsky et al, 2005). In both preterm and term baboon neonates, the calyx of Held terminal exhibited thick, finger-like processes, as observed in adult rhesus monkey.…”

“…Preterm baboons were delivered at 67% of gestation at the Texas Biomedical Research Institute in San Antonio. Preterm baboon care was recently described in detail (Blanco et al, 2013). Briefly, term baboons were naturally delivered (at 185 d GA), whereas preterm baboons were delivered via cesarean section at 125 Ϯ 2 d GA (67% of GA) and were intubated immediately after birth and chronically ventilated for a planned survival of 14 d in a neonatal intensive care unit.…”

“…Central intravenous lines were placed shortly after birth for fluid management and parenteral nutrition. Preterm baboons were treated with corticosteroids, antibiotics, ketamine, valium, vitamin K, and blood transfusions (Blanco et al, 2013).…”

Immunohistochemical Localization of Calbindin D28k, Parvalbumin, and Calretinin in the Superior Olivary Complex of Circling Mice

“…CB-IR neurons were prominent in principal neurons of the MNTB throughout different mammalian species, e.g., humans [Kulesza, 2014], rhesus monkeys [Bazwinsky et al, 2005], bats [Zettel et al, 1991], cats [Adams and Mugnaini, 1990;Matsubara, 1990], chinchillas [Kelley et al, 1992], rats [Webster et al, 1990;Friauf, 1994], and guinea pigs [Caicedo et al, 1996]. Likewise, CB-IR neurons were observed in the medial superior olive (MSO) of the bat [Zettel et al, 1991], whereas CB-IR neurons were not detected in the adult rat [Friauf, 1994], guinea pig [Caicedo et al, 1996], and cat [Adams and Mugnaini, 1990;Matsubara, 1990].…”

“…Relative to key functions in the auditory brain stem, CaBPs, e.g., calbindin D28k (CB), parvalbumin (PV), and calretinin (CR) distributions were broadly investigated to elucidate expression patterns in different SOC nuclei as well as distinct neuronal morphology by using immunohistochemistry in humans [Bazwinsky et al, 2003;Kulesza, 2014], rhesus monkeys [Bazwinsky et al, 2005], bats [Vater and Braun, 1994], rats [Lohmann and Friauf, 1996], mice [O'Neill et al, 1997], guinea pigs [Caicedo et al, 1996], gerbils, and opossum [Bazwinsky-Wutschke et al, 2016]. Ebbers et al [2015] validated that targeted deletion of Ca v 1.2 in the auditory brain stem resulted in postnatal cell death and a decrease in volume and cell numbers of auditory nuclei although auditory brain stem responses were nearly normal [Ebbers et al, 2015].…”