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Cardiovascular changes in response to ovarian stimulation
Abstracts
disruption and possible relation to recent changes observed in Sjogren and Ross syndromes will be presented. doi:10.1016/j.autneu.2007.06.026
S4-1 Autonomic hypersensitivity and pain-related synaptic plasticity in the central nucleus of amygdala Fusao Kato a, Yukari Takahashi a, Nami Hasegawa a, Ryo Ikeda a,b a Lab. Neurophysiol., Department Neurosci., Jikei University School of Medicine, Tokyo, Japan b Department Orthopaed., Jikei University School of Medicine, Japan Pain sensation is inevitably liked to negative emotion, which is followed by various types of specific autonomic responses. Lines of evidence indicate that the ascending pathway from the nociceptive neurons in the laminae I and II of the spinal cord to the laterocapsular part of the central amygdala (CeA) via the lateral nucleus of the parabrachialis (NPB) plays essential role in the link between pain sensation and emotional responses (Gauriau and Bernard, 2002; Neugebauer et al., 2003). It is therefore likely that this pathway also plays an important role in expression of pain-related autonomic behaviours because the central amygdala primarily underlies emotion-related autonomic responses. We have recently demonstrated that in animal model of chronic neuropathic pain, excitatory synaptic transmission between the afferent fibers arising from the NPB and CeA neurons is potentiated in a manner dependent on the degree of neuropathic pain symptom (Ikeda et al., Pain, 2007). Unlike in acute pain models, this potentiation was independent of NMDA receptor hyperactivity, suggesting that structural changes of AMPA receptor-mediated synaptic transmission underlie such consolidation of painrelated synaptic plasticity. In the animals with neuropathic pain, a mechanical touch of the hindpaw ipsilateral to the neuropathic pain at sub-threshold intensity for the allodynic responses immediately increased heart rate fluctuation. These results suggest that potentiated synaptic connectively between nociception-related inputs and CeA neurons also leads to enhanced autonomic responses to potentially noxious somatic sensation. doi:10.1016/j.autneu.2007.06.027
S4-2 Cardiovascular changes in response to ovarian stimulation Sae Uchida a, Fusako Kagitani a, Atsuko Suzuki b, Harumi Hotta a a Department of the Autonomic Nervous System, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan b Laboratory of Physiology, Health Science University, Yamanashi, Japan
29
Noxious afferent stimulation of the uterus has been reported to produce cardiovascular reflexes in rats (Robbins and Sato, 1991). Recently, we reported functional evidence of autonomic efferent nerves innervating the ovary (Uchida et al., 2003), and, since torsion or ischemia of the ovary is known to cause cardiovascular responses clinically, ovarian afferents may have physiological role. In the present study, we examined cardiovascular responses to ovarian afferent stimulation in rats. Nonpregnant adult rats were anesthetized with pentobarbital and artificially ventilated. Arterial blood pressure and heart rate were monitored continuously. The ovary was stimulated for 30 s by either the topical application of bradykinin (10−4 M) to the surface of the ovary using a small cotton swab or by pulling the suspensory ligament and the base of ovary. Ovarian afferent stimulation caused a decrease in heart rate (about 15 beats/min) and blood pressure (about 20 mm Hg). The ovarian plexus nerve (OPN), which contains autonomic nerves innervating the ovary, was cut and the proximal end was electrically stimulated. When the stimulus was adequate to excite unmyelinated C (or group IV) afferent fibers, a decrease in heart rate and blood pressure was observed that was similar to that induced by chemical and mechanical stimulation. The decrease in heart rate and blood pressure induced by OPN stimulation was not affected by severing the bilateral vagal nerves at the cervical level. These results indicate that afferent C fibers in the ovarian plexus nerve convey noxious information from the ovary and mediate a reflexive decrease in heart rate and blood pressure. The efferent pathway of this ovarian-cardiovascular reflex may be cardiovascular sym pathetic pathways and not cardiac parasympathetic (vagal) nerves. doi:10.1016/j.autneu.2007.06.028
S4-3 Autonomic control of the heart during stress: Role of central serotonin receptors Eugene Nalivaiko Flinders University, Australia Involvement of central serotonergic (5-HT) neurotransmission in cardiac control is well documented. However, most of previous studies were conducted in anaesthetized animals, and thus it is not known whether central 5-HT receptors are involved in the control of cardiac autonomic outflow in conscious state, and especially during psychological stresses. We used several animal models of acute psychological stresses, and assessed effects of systemic and local intra-brain administration of agonists and antagonists of 5-HT1A and 5-HT2A receptors on stress-induced cardiac changes. We found that in conscious rabbits and rats, selective activation of 5-HT1A receptors has no or minor hemodynamic effects at rest. In contrast, during air jet stress (rabbits) and restraint stress and social defeat stress (rats)
disruption and possible relation to recent changes observed in Sjogren and Ross syndromes will be presented. doi:10.1016/j.autneu.2007.06.026
S4-1 Autonomic hypersensitivity and pain-related synaptic plasticity in the central nucleus of amygdala Fusao Kato a, Yukari Takahashi a, Nami Hasegawa a, Ryo Ikeda a,b a Lab. Neurophysiol., Department Neurosci., Jikei University School of Medicine, Tokyo, Japan b Department Orthopaed., Jikei University School of Medicine, Japan Pain sensation is inevitably liked to negative emotion, which is followed by various types of specific autonomic responses. Lines of evidence indicate that the ascending pathway from the nociceptive neurons in the laminae I and II of the spinal cord to the laterocapsular part of the central amygdala (CeA) via the lateral nucleus of the parabrachialis (NPB) plays essential role in the link between pain sensation and emotional responses (Gauriau and Bernard, 2002; Neugebauer et al., 2003). It is therefore likely that this pathway also plays an important role in expression of pain-related autonomic behaviours because the central amygdala primarily underlies emotion-related autonomic responses. We have recently demonstrated that in animal model of chronic neuropathic pain, excitatory synaptic transmission between the afferent fibers arising from the NPB and CeA neurons is potentiated in a manner dependent on the degree of neuropathic pain symptom (Ikeda et al., Pain, 2007). Unlike in acute pain models, this potentiation was independent of NMDA receptor hyperactivity, suggesting that structural changes of AMPA receptor-mediated synaptic transmission underlie such consolidation of painrelated synaptic plasticity. In the animals with neuropathic pain, a mechanical touch of the hindpaw ipsilateral to the neuropathic pain at sub-threshold intensity for the allodynic responses immediately increased heart rate fluctuation. These results suggest that potentiated synaptic connectively between nociception-related inputs and CeA neurons also leads to enhanced autonomic responses to potentially noxious somatic sensation. doi:10.1016/j.autneu.2007.06.027
S4-2 Cardiovascular changes in response to ovarian stimulation Sae Uchida a, Fusako Kagitani a, Atsuko Suzuki b, Harumi Hotta a a Department of the Autonomic Nervous System, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan b Laboratory of Physiology, Health Science University, Yamanashi, Japan
29
Noxious afferent stimulation of the uterus has been reported to produce cardiovascular reflexes in rats (Robbins and Sato, 1991). Recently, we reported functional evidence of autonomic efferent nerves innervating the ovary (Uchida et al., 2003), and, since torsion or ischemia of the ovary is known to cause cardiovascular responses clinically, ovarian afferents may have physiological role. In the present study, we examined cardiovascular responses to ovarian afferent stimulation in rats. Nonpregnant adult rats were anesthetized with pentobarbital and artificially ventilated. Arterial blood pressure and heart rate were monitored continuously. The ovary was stimulated for 30 s by either the topical application of bradykinin (10−4 M) to the surface of the ovary using a small cotton swab or by pulling the suspensory ligament and the base of ovary. Ovarian afferent stimulation caused a decrease in heart rate (about 15 beats/min) and blood pressure (about 20 mm Hg). The ovarian plexus nerve (OPN), which contains autonomic nerves innervating the ovary, was cut and the proximal end was electrically stimulated. When the stimulus was adequate to excite unmyelinated C (or group IV) afferent fibers, a decrease in heart rate and blood pressure was observed that was similar to that induced by chemical and mechanical stimulation. The decrease in heart rate and blood pressure induced by OPN stimulation was not affected by severing the bilateral vagal nerves at the cervical level. These results indicate that afferent C fibers in the ovarian plexus nerve convey noxious information from the ovary and mediate a reflexive decrease in heart rate and blood pressure. The efferent pathway of this ovarian-cardiovascular reflex may be cardiovascular sym pathetic pathways and not cardiac parasympathetic (vagal) nerves. doi:10.1016/j.autneu.2007.06.028
S4-3 Autonomic control of the heart during stress: Role of central serotonin receptors Eugene Nalivaiko Flinders University, Australia Involvement of central serotonergic (5-HT) neurotransmission in cardiac control is well documented. However, most of previous studies were conducted in anaesthetized animals, and thus it is not known whether central 5-HT receptors are involved in the control of cardiac autonomic outflow in conscious state, and especially during psychological stresses. We used several animal models of acute psychological stresses, and assessed effects of systemic and local intra-brain administration of agonists and antagonists of 5-HT1A and 5-HT2A receptors on stress-induced cardiac changes. We found that in conscious rabbits and rats, selective activation of 5-HT1A receptors has no or minor hemodynamic effects at rest. In contrast, during air jet stress (rabbits) and restraint stress and social defeat stress (rats)