Prilocaine hydrochloride

Prilocaine hydrochloride is a local anesthetic of the amino amide type.

Prilocaine hydrochloride protects zebrafish from lethal effects of ionizing radiation: role of hematopoietic cell expansion.[Pubmed:25843444]

Tokai J Exp Clin Med. 2015 Mar 20;40(1):8-15.

Drug repositioning is an approach of significant translatability, and the present study was undertaken to screen a collection of FDA approved small-molecule clinical compounds for identification of novel radioprotective agents. Screening of JHCCL (Johns Hopkins Clinical Compound Library), a collection of 1,400 FDA approved small molecules, lead to identification of Prilocaine hydrochloride, a local anesthetic used widely during dental procedures, as a potential radioprotector. Prilocaine, at a concentration of 20 microM, protected zebrafish from radiation induced (20 Gy) pericardial edema (PE), microphthalmia and rendered 60 % survival advantage over radiation exposed controls. While 40 % survival advantage over radiation exposed controls was achieved with 10 microM prilocaine. Prilocaine, in a dose-dependent manner, scavenged, radiation-induced hydroxyl radicals and maximally (43 %) at the highest concentration (1 mM) tried in this study. However, prilocaine exerted a mild superoxide anion scavenging potential (around 5 %) at all the concentrations used within this study. Prilocaine, at 20 microM concentration, significantly increased erythropoiesis, a marker for HSC function, in caudal hematopoietic tissue (CHT) in wild type and anemic zebrafish embryos (1.48 and 0.85 folds respectively) when compared to untreated (1) and phenylhydrazine (PHZ) (0.41 fold) treated control groups respectively. These results suggest that prilocaine is a radioprotective agent and free radical scavenging and HSC expanding potential seems to be contributing towards its radioprotective action.

Verification of protector effect of the norepinephrine and felypressin upon the cardiovascular system under action of the lidocaine hydrochloride and prilocaine hydrochloride in anesthetized rats.[Pubmed:12220948]

Pharmacol Res. 2002 Aug;46(2):107-11.

Vasoconstrictor substances, as norepinephrine and epinephrine, were mixtured to local anesthetics to decrease their toxic effects and to prolong the depth of the anesthesia. However, these catecholamines produce systolic and diastolic hypertension. The effects of felypressin, a synthetic vasoconstrictor, upon arterial blood pressure and heart are lesser than those of norepinephrine or epinephrine, but due to its effects like oxytocin these catecholamines are yet the most used vasoconstrictors in association with lidocaine or another anesthetic salt. These vasoconstrictors are contraindicated for some physician, mainly for cardiac patients. But, are the catecholamines or is the salt the most dangerous components of the local anesthetic? The effects of the salt and catecholamines are opposite, but which of these exercises their effects first when inside blood vessel? Singi et al. [Pharmacol. Res. 44 (2001)] demonstrated that the first effect is always of the salt and that norepinephrine promotes protector effects upon guinea-pig isolated heart against lidocaine action. But, is this true for in vivo animals? The present study was performed with the aiming to answer this question and to verify if felypressin can induce the same effect of the norepinephrine. Fourteen Rattus norvegicus albinus, weighing 350g on average, were used. After being anesthetized with sodic thiopental, they were tracheostomizeds and one jugular and one carotid were cannuled for application of substances and to record the blood arterial pressure, respectively. The ECG was gotten through electrodes located in the front and back paws of the animals. The animals were separated in two groups, each one with seven rats. The lidocaine hydrochloride 2% in the doses of 600 microg and 3% in the doses of 900 microg acted on the cardiovascular system reducing the arterial pressure and modifying the electrocardiogram, while the Prilocaine hydrochloride, in the same doses, also reduced the arterial pressure, but did not modify the electrocardiogram. When norepinephrine was associated to lidocaine 3% hydrochloride, it was possible to observe that this salt always exercised its effect first and a protective effect against the fall of pressure produced for the lidocaine. The same protective effect did not occur when felypressin was associated with Prilocaine hydrochloride 3%.