The present study was planned to evaluate role of tachykinins (TKs) and neurokinin (NK) receptors in the regulation of gastric motility in sheep. We examined the effects of intravenous (i.v.) injection of neurokinin A (NKA) and substance P (SP) on motility of the rumen, omasum, and abomasum in conscious sheep and the effects of NK receptor blockade on the effect of TKs using NK-1 receptor antagonist L-732,138 and NK-2 receptor antagonist SR48968. Moreover, the effect of NK receptor blockade on omasal cyclic contractions was examined. Intravenous injection of NKA and SP induced tonic contraction of rumen, omasum, and abomasum, and the contractile effect of NKA was more potent than that of SP in all the gastric regions. Although the effect of SP was not inhibited by L-732,138, the effect of NKA was significantly inhibited by SR48968. However, single infusion of SR48968 and L-732,138 did not alter cyclic electromyographic activity and basal intraluminal pressure in the omasum. These results imply that NKA and NK-2 receptors play a primary role in non-cholinergic regulation of ovine gastric motility, though NK-2 and NK-1 receptors seem unlikely to be involved in the physiological regulation of omasal cyclic contractions.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.npep.2012.07.005 | DOI Listing |
Int J Neuropsychopharmacol
January 2025
Institute of Physiology, Medical School, University of Pécs, Pécs, Hungary.
Background: The tachykinin substance P (SP) facilitates learning and memory processes after its central administration. Activation of its different receptive sites, neurokinin-1 receptors (NK1Rs), as well as NK2Rs and NK3Rs was shown to influence learning and memory. The basal ganglia have been confirmed to play an important role in the control of memory processes and spatial learning mechanisms, and as part of the basal ganglia, the globus pallidus (GP) may also be involved in this regulation.
View Article and Find Full Text PDFExp Eye Res
January 2025
Laboratory of Ocular Immunology, Transplantation and Regeneration, Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA. Electronic address:
Substance P (SP) expressed by corneal nerves, is an 11-amino acid long neuropeptide from the tachykinin family, encoded by the Tac1 gene, and binds to neurokinin receptors. SP overexpression is associated with various pathological responses in the cornea including vasodilation, pain, inflammation, and angiogenesis in the normally avascular tissue. This study investigates the role of neurokinin-1 receptor (NK-1R) mediated signaling in nociception, nerve regeneration, and neuronal activation following mechanical corneal injury in mice.
View Article and Find Full Text PDFTheranostics
January 2025
Department of Pathophysiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
: The periaqueductal gray (PAG) is a central hub for the regulation of aggression, whereas the circuitry and molecular mechanisms underlying this regulation remain uncharacterized. In this study, we investigate the role of a distinct cell type, -expressing (Tac2) neurons, located in the dorsomedial PAG (dmPAG) and their modulation of aggressive behavior in mice. : We combined activity mapping, Ca recording, chemogenetic and pharmacological manipulation, and a viral-based translating ribosome affinity purification (TRAP) profiling using a mouse resident-intruder model.
View Article and Find Full Text PDFPituitary
December 2024
Research Laboratory on Neuropeptides, Institute of Biomedicine of Seville (IBIS), Seville, Spain.
Background: Human adamantinomatous craniopharyngioma (ACP) is a brain tumor that originates at the base of the skull and shows aggressive local behavior, invading sensitive structures such as the optic pathways and hypothalamus. The conventional treatment of the tumor has been surgery and radiotherapy with the consequent development of serious sequelae. It is well known that Substance P (SP) peptide and Neurokinin-1 receptor (NK-1R) are involved in inflammation and cancer progression and its blockage with NK-1R antagonists has been shown to effectively counteract tumor development in preclinical trials.
View Article and Find Full Text PDFNeuron
December 2024
Department of Anesthesiology, Huashan Hospital, State Key Laboratory of Medical Neurobiology, Institute for Translational Brain Research, MOE Frontiers Center for Brain Science, Fudan University, Shanghai 200032, China. Electronic address:
The lateral parabrachial nucleus (PBN) is critically involved in neuropathic pain modulation. However, the cellular and molecular mechanisms underlying this process remain largely unknown. Here, we report that in mice, the right-sided, but not the left-sided, PBN plays an essential role in the development of hyperalgesia following nerve injury, irrespective of the injury side.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!