Fetal and offspring arrhythmia following exposure to nicotine during pregnancy

Abstract

Although recent studies have demonstrated prenatal nicotine can increase cardiovascular risk in the offspring, it is unknown whether exposure to nicotine during pregnancy also may be a risk for development of arrhythmia in the offspring. In addition, in previous studies of fetal arrhythmia affected by smoking, only two patterns, bradycardia and tachycardia, were observed. The present study examined acute effects of maternal nicotine on the fetal arrhythmia in utero, and chronic influence on offspring arrhythmia at adult stage following prenatal exposure to nicotine. Nicotine was administered to pregnant ewes and rats. In the fetal sheep, intravenous nicotine not only induced changes of fetal heart rate, but also caused cardiac cycle irregularity, single and multiple dropped cardiac cycles. Although maternal nicotine had no influence on fetal blood pH, lactic acid, hemocrit, Na(+), K(+) levels and plasma osmolality, fetal blood PO(2) levels were significantly decreased following maternal nicotine in ewes. In offspring rats at 4-5 months after birth, prenatal exposure to nicotine significantly increased heart rate and premature ventricular contraction in restraint stress. In addition, arrhythmias induced by injection of nicotine were higher in the offspring prenatal exposure to nicotine in utero. The results provide new evidence that exposure to nicotine in pregnancy can cause fetal arrhythmia in various patterns besides tachycardia and bradycardia, the possible mechanisms for nicotine-induced fetal arrhythmia included in utero hypoxia. Importantly, following exposure to nicotine significantly increased risk of arrhythmia in the adult offspring. The finding offers new insight for development of cardiac rhythm problems in fetal origins.

Air quality in New York City hookah bars

“…Potentially, cigarette smoking by patrons and employees in back rooms may occur, but no cigarette smoking was observed in the main room of the hookah bars surveyed in this study. In addition to its potential for addiction and as a gateway to the use of other tobacco products, nicotine is known to have myriad harmful health consequences, such as teratogenic effects on neurodevelopment,43 44 ‘altering the formation, survival, and differentiation of brain cells, eliciting deficits in structure, synaptic function and behavioral performance’,45 and alteration in neurotransmitters,46 as well as being associated with fatal arrhythmias,47 low birth weight from prenatal exposure,48 hearing loss,49 tooth decay50 and hyperactivity 51 52…”

Prenatal Exposure to Nicotine in Pregnant Rat Increased Inflammatory Marker in Newborn Rat

“…Also exposing pregnant rats to nicotine caused an increase in the secretion of sympathetic neurotransmitters of their newborns and, by suppressing the PKC gene, caused rising of cardiac complications in their embryo [4]. Some other studies have reported the effects of prenatal exposure of rats to nicotine and its associated effects on cardiovascular system such as tachycardia, arrhythmia, ischemia, and atherosclerosis [27–30]. Totally, all nicotine exposed groups showed disturbances of the serum levels of all the evaluated inflammatory markers in comparison with the nonexposed group and a dose dependent trend was seen among almost all the evaluated markers in exposed rats.…”

Zebrafish as a Vertebrate Model System to Evaluate Effects of Environmental Toxicants on Cardiac Development and Function

“…Embryos were exposed to different concentrations of nicotine solutions (50 µM, 100 µM, and 1.2 mM) and heart rates were measured after 5 min of nicotine exposure. Like cocaine, nicotine exposure showed dose-dependent effect on heart function, causing tachycardia at lower doses and bradycardia at higher doses [34], resembling the types of arrhythmia previously observed in other model organisms [91]. However, chronic exposure to nicotine from 2–48 hpf reduced the heartbeat of embryos at later stages, an effect possibly due to the malformed heart [34].…”