Vasoactive therapy

Patients receiving monoamine oxidase inhibitors (MAOI) as antidepressant therapy have been especially subject to the hypertensive effects of vasoactive amines (52). These dietary amines have also been impHcated as causative agents ia migraine. Other aaturaHy occurring alkaloids (qv) have been recognized for centuries as possessing neurological stimulant and depressant properties. 

The triptans are considered specific therapies in that they target the pathophysiology underlying migraine.33 They abort headache through beneficial effects on neuronal imbalances.11 Triptans inhibit neurotransmission in the trigeminal complex and activate serotonin lb/Id pathways that modulate nociception in the brain stem. They also decrease the release of vasoactive peptides leading to vascular reactivity and pain.34 Triptans are a welcome addition to the therapeutic armamentarium in that they are available in intranasal, subcutaneous, and oral... 

Vasoactive drug therapy (somatostatin, octreotide, or terlipressin) to stop or slow bleeding is routinely employed early in patient management to allow stabilization of the patient and to permit endoscopy to proceed under more favorable conditions. These agents decrease splanchnic blood flow and reduce portal and variceal pressures, without significant adverse effects. 

EBL is the recommended form of endoscopic therapy for acute esophageal variceal bleeding and should be used in conjunction with vasoactive drug therapy Secondary prophylaxis of variceal bleeding... 

Numerous cases have been reported in which latanoprost therapy has been associated with the development of cystoid macular edema (CME). Considering the role that prostaglandins play in the pathogenesis of CME, it may be reasonable to assume that topically applied latanoprost can increase the risk of CME. However, latanoprost itself is not known to be vasoactive or to affect vascular permeability. Furthermore, pharmacokinetic studies have feiled to demonstrate significant levels of latanoprost in the posterior segment of the eye after topical application. Indeed, controlled clinical studies... 

The effects of both ACh and NE can be enhanced by the CO-localization of agents such as the neuropeptides vasoactive intestinal peptide (VIP) and neuropeptide Y (NPY). For example, VIP can increase ACh induced salivary secretion (Lundberg and Hokfelt, 1983) and NPY can enhance the vasoconstrictive effects of NE (Wahlestedt et al., 1985). In theory, agents mimicking or blocking the effects of these neuropeptides should expand the opportunities for conh ol of various disease conditions such as Sjogren s disease and hypertension. How ever, significant advances in such therapy are yet to be realized. 

Vasopressin is rapidly cleared from the circulation and must be given by continuous i.v. infusion. The synthetic ancJogue, terlipressin (triglycyl-lysine-vasopressin) is now preferred. This prodrug (or hormogen) is converted in vivo to the vasoactive lysine vasopressin which has biological activity for 3-4 hours, and is effective by bolus injections 4-hourly, usually for 48-72 hours. It is a useful adjunct to endoscopic therapy and reduces rebleeding. 

The vasoactive amines phentolamine and papaverine are occasionally used as intracavernosal therapy, usually in combination with alprostadil, although their use for erectile dysfunction is off-label. Moxisylyte is another vasoactive agent used as intracavernosal therapy. The drug is approved in several European countries, but is not approved in the United States. The advantages over alprostadil are that with moxisylyte, sexual stimulation is still required to achieve full erection and that detumescence occurs on ejaculation. 

Variceal bleeding Pharmacologic prophylaxis Endoscopy, vasoactive drug therapy (octreotide), sclerotherapy, volume resuscitation, pharmacologic prophylaxis Child-Pugh score, endoscopy, CBC CBC, evidence of overt bleeding Appropriate reduction in heart rate and portal pressure Acute control acute bleed Chronic variceal obliteration, reduce portal pressures... 

Hydralazine, a vasodilator in clinical use, has been the most intensively studied of the vasoactive agents in targeting tumor blood flow as an approach for cancer therapy. Hydralazine inhibits tumor blood flow in a number of murine tumors, giving a maximum inhibition of 80-90% at doses between 2.5 and 5 mg/kg (30,31). However, at doses of <1 mg/kg, hydralazine increases tumor blood flow (31). Effects were seen within 15 min of administration, were main-... 

Drugs used for intracavernous vasoactive injection therapy... 

Vasoactive intestinal peptide tumors (VIPomas)— Treatment of the profuse watery diarrhea associated with VIP-secreting tumors. Significant improvement has been noted in the overall condition of these otherwise therapeutically unresponsive patients. Therapy with octreotide results in improvement in electrolyte abnormalities (e.g., hypokalemia), often enabling reduction of fluid and electrolyte support. 

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