Robert M. Boyar
Encyclopedia
Robert M. Boyar was a physician and endocrinologist known for his studies of the neuroendocrinology
Neuroendocrinology
Neuroendocrinology is the study of the extensive interactions between the nervous system and the endocrine system, including the biological features of the cells that participate, and how they functionally communicate...

 of puberty.

Early years and education

Boyar received his MD from Albert Einstein College of Medicine
Albert Einstein College of Medicine
Albert Einstein College of Medicine is a graduate school of Yeshiva University. It is a not-for-profit, private, nonsectarian medical school located on the Jack and Pearl Resnick Campus in the Morris Park neighborhood of the borough of the Bronx of New York City...

, Bronx, New York, 1962. He was a Navy physician during the Vietnam War
Vietnam War
The Vietnam War was a Cold War-era military conflict that occurred in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. This war followed the First Indochina War and was fought between North Vietnam, supported by its communist allies, and the government of...

, and on the medical staff of Montefiore Medical Center
Montefiore Medical Center
Montefiore Medical Center, in the Bronx, New York, is the University Hospital for the Albert Einstein College of Medicine. The hospital, named for Moses Montefiore, is one of the 50 largest employers in New York State . In 2011, Montefiore Medical Center was ranked as #6 of the 180 New York City...

. For 2½ years he was Associate Professor of Internal Medicine, University of Texas Southwestern Medical School, Dallas.

Scientific discoveries

Boyar is best known for his studies of gonadotropin
Gonadotropin
Gonadotropins are protein hormones secreted by gonadotrope cells of the pituitary gland of vertebrates. This is a family of proteins, which include the mammalian hormones follitropin , lutropin , placental chorionic gonadotropins hCG and eCG and chorionic gonadotropin , as well as at least two...

 secretion in puberty. An American physiologist, Ernst Knobil, discovered that the anterior pituitary produces pulses of Luteinizing hormone
Luteinizing hormone
Luteinizing hormone is a hormone produced by the anterior pituitary gland. In females, an acute rise of LH called the LH surge triggers ovulation and development of the corpus luteum. In males, where LH had also been called interstitial cell-stimulating hormone , it stimulates Leydig cell...

 (LH) at about hourly intervals. The LH pulses are the consequence of pulsatile gonadotropin releasing hormone (GnRH) secretion by the hypothalamus into the pituitary portal circulation that, in turn, is the result of an oscillator or signal generator in the central nervous system ("GnRH pulse generator"). Boyar demonstrated that in children approaching puberty the Luteinizing Hormone pulses occur only during sleep. This sleep related gonadotropin secretion initiates testosterone
Testosterone
Testosterone is a steroid hormone from the androgen group and is found in mammals, reptiles, birds, and other vertebrates. In mammals, testosterone is primarily secreted in the testes of males and the ovaries of females, although small amounts are also secreted by the adrenal glands...

 secretion in boys and
estradiol
Estradiol
Estradiol is a sex hormone. Estradiol is abbreviated E2 as it has 2 hydroxyl groups in its molecular structure. Estrone has 1 and estriol has 3 . Estradiol is about 10 times as potent as estrone and about 80 times as potent as estriol in its estrogenic effect...

 secretion in girls, which ultimately result in the clinical characteristics
associated with human puberty. Some investigators have attributed the onset of puberty to a resonance
Resonance
In physics, resonance is the tendency of a system to oscillate at a greater amplitude at some frequencies than at others. These are known as the system's resonant frequencies...

 of oscillator
Oscillation
Oscillation is the repetitive variation, typically in time, of some measure about a central value or between two or more different states. Familiar examples include a swinging pendulum and AC power. The term vibration is sometimes used more narrowly to mean a mechanical oscillation but sometimes...

s in the brain. By this mechanism, the gonadotropin pulses that occur during sleep in puberty represent beats
Beat (acoustics)
In acoustics, a beat is an interference between two sounds of slightly different frequencies, perceived as periodic variations in volume whose rate is the difference between the two frequencies....

.
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