Modulation of the activity of midbrain central gray substance neurons by calcium channel agonists and antagonists in vitro

Headache in the presentation of noncephalic acute illness

Background:

Headache is a frequent symptom of many systemic diseases that do not involve cranial structures. In this observational study, we assessed factors associated with headache in the acute presentation of systemic conditions in a nonsurgical emergency department (ED).

Methods:

Consecutive patients, admitted to Soroka University Medical Center ED due to noncephalic illness, were prospectively surveyed using a structured questionnaire focused on the prevalence and characteristics of headache symptoms. Medical data were extracted from the patient's charts.

Results:

Between 1 and 6/2012, 194 patients aged 64.69 ± 19.52 years, were evaluated. Headache was reported by 83 (42.7%) patients and was more common among patients with febrile illness (77.5% vs. 22.5%, P < 0.001). Respiratory illness and level of O₂ saturation were not associated with headache. Headache in the presentation of a noncephalic illness was associated with younger age (58 vs. 69, P < 0.001) and with suffering from a primary headache disorder (48.2% vs. 10.8%, P < 0.001). Headache was also associated with higher body temperature and lower platelets count.

Conclusions:

Headache is a common symptom in acute noncephalic conditions and was found to be associated with younger age and febrile disease on presentation. Patients who present with primary headache disorders are more prone to have headache during acute illness. Acute obstructive respiratory disease, hypercarbia or hypoxemia were not associated with headache.

Effects of antagonists to high-threshold calcium channels upon spinal mechanisms of pain, hyperalgesia and allodynia

High-threshold voltage-dependent calcium channels enable calcium ions to enter neurons upon depolarization and thereby influence synaptic mediator/receptor systems, membrane excitability levels, second and third messenger concentration, and gene expression. These phenomena underlie several processes including those of normal nociception and of hyperalgesia and allodynia. The present article deals with the role of spinal L-, N- and P/Q-type calcium channels in short-lasting nociception as well as in the hyperalgesia and allodynia elicited by chemical irritants of peripheral nociceptors, inflammatory and mechanical lesions of peripheral tissues, and lesions of peripheral nerves. The studies summarized herein are based on the spinal delivery of specific antagonists to high-threshold calcium channels, and reveal that blockade of L-type, P/Q-type and, particularly, N-type channels can prevent, attenuate, or both, subjective pain as well as primary and/or secondary hyperalgesia and allodynia in a variety of experimental and clinical conditions.