Distribution of Neurotensin and Somatostatin-28 (1-12) in the Minipig Brainstem

Abstract

Using an indirect immunoperoxidase technique, an in depth study has been carried out for the first time on the distribution of fibres and cell bodies containing neurotensin and somatostatin-28 (1-12) (SOM) in the minipig brainstem. The animals used were not treated with colchicine. The distribution of neurotensin- and SOM-immunoreactive fibres was seen to be quite similar and was moderate in the minipig brainstem: a close anatomical relationship between both neuropeptides was observed. The distribution of cell bodies containing neurotensin or SOM was quite different and restricted. Cell bodies containing neurotensin were found in four brainstem nuclei: nucleus centralis raphae, nucleus dorsalis raphae, in the pars centralis of the nucleus tractus spinalis nervi trigemini and in the nucleus ventralis raphae. Cell bodies containing SOM were found in six nuclei/regions of the brainstem: nucleus ambiguus, nucleus dorsalis motorius nervi vagus, formatio reticularis, nucleus parabrachialis medialis, nucleus reticularis lateralis and nucleus ventralis raphae. According to the observed anatomical distribution of the immunoreactive structures containing neurotensin or SOM, the peptides could be involved in sleep-waking, nociceptive, gustatory, motor, respiratory and autonomic mechanisms.

Immunohistochemical mapping of neurotensin in the alpaca diencephalon

“…The distribution of immunoreactive structures containing calcitonin gene-related peptide (CGRP), adrenocorticotropic hormone (ACTH), leucine-enkephalin, beta-endorphin (1-27), alpha-melanocyte-stimulating hormone (aMSH) or alpha-neo-endorphin and somatostatin-28 (1-12) has been previously reported in the alpaca diencephalon [27,28,32]. In all the thalamic and hypothalamic nuclei in which we have observed neurotensin-immunoreactive fibers, the presence of fibers containing beta-endorphin , aMSH, alpha-neo-endorphin or somatostatin-28 (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12) has been also reported [27,28,32]. Moreover, fibers containing CGRP, ACTH, or leucine-enkephalin [28,32] were observed in all the hypothalamic nuclei in which we have visualized neurotensin-immunoreactive fibers.…”

“…3b); 2) omitting the neurotensin antiserum in the first incubation bath (Fig. 3e); and 3) preabsorption of anti-neurotensin with an excess (10 -7 M) of synthetic substance P, angiotensin II, beta-endorphin, somatostatin-28 (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12), vasoactive intestinal peptide, and neuropeptide Y (Sigma-Aldrich). In all cases, the results confirmed the specificity of the antisera used in this study.…”

“…Many immunohistochemical and radioimmunoassay studies have been carried out on the distribution of the tridecapeptide neurotensin in the mammalian central nervous system [1][2][3][4][5][6][7][8][9][10][11]. In the species studied (e.g., rat, guinea pig, cat, minipig, monkey, man), these works have reported a widespread distribution of neurotensin in the central nervous system and this suggests that the peptide might be involved in many physiological actions.…”

“…In the species studied (e.g., rat, guinea pig, cat, minipig, monkey, man), these works have reported a widespread distribution of neurotensin in the central nervous system and this suggests that the peptide might be involved in many physiological actions. In fact, neurotensin, acting as a neurotransmitter and/or neuromodulator, has been involved in several physiological actions affecting hemodynamic, neuroendocrine, food intake, nociceptive, thermoregulatory, locomotor, respiratory, sleep-waking, gustatory, memory, auditory and glucoregulatory systems [1,9,[12][13][14][15][16]. Moreover, it is known that neurotensin promotes the dendritic spine maturation and dendrite elongation [17] and modulates high-voltage-activated calcium currents [18].…”

“…Moreover, since 2007, the chemical neuroanatomy of neuropeptides in the alpaca CNS has increased considerably. Using immunohistochemical (IHC) techniques, the distribution of calcitonin gene-related peptide, somatostatin-28 (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12), leucine-enkephalin, adrenocorticotropic hormone, beta-endorphin , alpha-melanocyte-stimulating hormone and alpha-neo-endorphin has been reported in the alpaca's CNS [27][28][29][30][31][32]. However, to date no data are currently available in the literature detailing the location of either fibers or cell bodies containing neurotensin in alpaca's diencephalon, a CNS region involved in many important functional mechanisms.…”