Pindolol Increases Plasma Norepinephrine Concentration by Stimulation of β2-Adrenoceptors in Conscious Spontaneously Hypertensive Rats

In chloralose anesthetized and paralyzed spontaneously hypertensive rats (SHR) a somatosympathetic reflex in the cervical sympathetic trunk elicited by a single electrical shock to forelimb afferent fibres in the median nerve was recorded. It has been shown that the somatosympathetic reflex consists of two responses and following silent period. The А-response evoked by the somatic myelinated afferent fibres stimulation, and C-respon.se elicited by the both stimulation of myelinated and unmyelinated afferent fibres. The silent period occurred with the myelinated fibres stimulation. Its duration was proportional to the electrical shock amplitude. The А-response consisted of four waves, the three of them formed early and late responses.

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Testosterone Increases: Sodium Reabsorption, Blood Pressure, and Renal Pathology in Female Spontaneously Hypertensive Rats on a High Sodium Diet

Advances in Pharmacological Sciences ◽

10.1155/2011/817835 ◽

2011 ◽

Vol 2011 ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

Bei Liu ◽

Daniel Ely

Keyword(s):

Blood Pressure ◽

Spontaneously Hypertensive Rats ◽

Sodium Reabsorption ◽

Plasma Norepinephrine ◽

Hypertensive Rats ◽

Spontaneously Hypertensive ◽

High Sodium ◽

Sodium Diet ◽

Hypertension Development ◽

High Sodium Diet

Estrogen (E) and testosterone (T) are important in the sexually dimorphic pattern of blood pressure (BP) development. The goal was to examine the effects of endogenous E and exogenous T in the development of hypertension in female spontaneously hypertensive rats (SHR) on a high sodium diet. Female SHR (, 5-week) were divided into four groups: (1) control (), (2) ovariectomized (OVX, ), (3) testosterone implants with intact ovaries (T, ), and (4) ovariectomized + testosterone implants (OVX+T, ). T was given immediately after OVX and replaced every two weeks and they were fed a 3% NaCl diet. BP was measured weekly and plasma norepinephrine (NE) analyzed by HPLC. OVX+T females exhibited the greatest elevation in BP (190 ± 4.0 mmHg) compared to controls at 15 weeks of age (140 ± 3.4 mmHg, ) and a pattern of hypertension development similar to that of male SHR. Females with T treatment showed evidence of glomerulosclerosis. In conclusion, T accelerated the development of hypertension similar to the BP pattern observed in males; the presence of ovaries attenuated the T induced increase in BP; T increased renal sodium reabsorption, and T increased glomerulosclerosis.

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Stimulation of atypical cannabinoid receptor GPR55 abolishes the symptoms of detrusor overactivity in spontaneously hypertensive rats

European Journal of Pharmaceutical Sciences ◽

10.1016/j.ejps.2020.105329 ◽

2020 ◽

Vol 150 ◽

pp. 105329

Author(s):

Andrzej Wróbel ◽

Anna Serefko ◽

Aleksandra Szopa ◽

Ewa Poleszak

Keyword(s):

Detrusor Overactivity ◽

Spontaneously Hypertensive Rats ◽

Cannabinoid Receptor ◽

Hypertensive Rats ◽

Spontaneously Hypertensive ◽

Stimulation Of

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Diminished sympathetic silent period in spontaneously hypertensive rats

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1979.236.3.r147 ◽

1979 ◽

Vol 236 (3) ◽

pp. R147-R152 ◽

Cited By ~ 1

Author(s):

L. P. Schramm ◽

G. N. Barton

Keyword(s):

Electrical Stimulation ◽

Sympathetic Activity ◽

Spontaneously Hypertensive Rats ◽

Silent Period ◽

Spontaneous Hypertension ◽

Hypertensive Rats ◽

Spontaneously Hypertensive ◽

Splanchnic Nerves ◽

Wistar Kyoto ◽

Stimulation Of

To determine if elevated sympathetic activity occurs in spontaneously hypertension, the silent period induced in splanchnic nerves following electrical stimulation of dorsal medullary sympathoexcitatory sites was compared in anesthetized normotensive Wistar Kyoto rats (WKYs) and Okamoto spontaneously hypertensive rats (SHRs). The strength of silent periods was defined as the degree of inhibition of responses to testing stimuli delivered at various latencies following conditioning trains, and it was assumed to be inversely related to the level of sympathetic activity. Weanling SHRs exhibited weaker silent periods than weanling WKYs although, at that age, the arterial pressures of the strains were not significantly different. Silent periods were also weaker in adult SHRs than in adult WKYs. This difference persisted after arterial pressures, which fell under anesthesia, were raised by phenylephrine infusions to the respective "normal" levels in each strain. These results support the hypothesis that elevated sympathetic activity exists during both the development and maintenance of spontaneous hypertension in rats.

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