. Patricio H. Contreras

Dr. . Patricio H. Contreras

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Research Focus & Metrics

Academic Career Length

46Years (1981-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 1985 in The Journal of Clinical Endocrinology & Metabolism
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.C. Patricio H. Contreras
. Patricio H. Contreras
EAElena Altieri
Elena Altieri
CLClaudio Liberman
Claudio Liberman
AGAlfredo Gac
Alfredo Gac
ARAuristela Rojas
Auristela Rojas
MSMaría Serón-Ferré
María Serón-Ferré
Ketoconazole, an imidazole derivative known to inhibit cytochrome P450-dependent adrenal enzymes was given to a patient with a functioning adrenal rest tumor of the liver in preparation for surgery. The drug was administered in a stepwise manner for 42 days starting with 400 mg and reaching 1 g the last 4 weeks of the trial. Clear clinical improvement was evident early in the trial and was associated with evidence of amelioration of her hypercortisolism and striking changes in serum and urinary levels of steroid hormones and metabolites. Sex steroids in serum and urine fell dramatically from the first day to the end of the trial. Urinary 17-ketosteroid excretion fell from a basal average of 139 mg'24 h to near normal levels within a week of therapy; serum testosterone fell from a basal level of 2.4 to 0.18 ng'ml; serum 17β-estradiol fell likewise from 1096 to 150 pg'ml. In contrast, cortisol levels in serum and urine increased in the first 2 weeks of the trial and subsequently fell to values below the basal levels. Similarly, serum 17α-OH-progesterone levels increased 63' above the basal levels by day 6 of the trial and declined afterwards. Nine months after successful tumor resection the patient is apparently cured as judged by steroid hormone levels and physical appearance. We conclude that ketoconazole was effective in blocking tumoral steroidogenesis which resulted in clinical benefit.

1 November 1983 in The Journal of Clinical Endocrinology & Metabolism
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Journal Article
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JLJ.H. Liu
J.H. Liu
KMK. Muse
K. Muse
.C. Patricio H. Contreras
. Patricio H. Contreras
DGD. Gibbs
D. Gibbs
WVW. Vale
W. Vale
SYS. S. C. Yen
S. S. C. Yen
In order to study the interaction between vasopressin (VP) and hypothalamic corticotropin releasing factor (CRF) on the release of ACTH, VP and CRF were administered separately and in combination to normal cycling women. The combined hormones raised plasma ACTH levels higher than the sum of the separate responses and 5 times more than CRF alone. This study reveals for the first time synergism between VP and CRF in their ACTH releasing effects in humans.

25 September 2007 in Human Reproduction
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Journal Article
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PVPilar Vigil
Pilar Vigil
.C. Patricio H. Contreras
. Patricio H. Contreras
JAJorge L. Alvarado
Jorge L. Alvarado
AGAna Godoy
Ana Godoy
ASAna M. Salgado
Ana M. Salgado
MCManuel E Cortés
Manuel E Cortés
Polycystic ovary syndrome (PCOS) is non-uniformly associated with insulin resistance (IR). We examined IR in women with PCOS. Sixty-nine PCOS women were subjected to the insulin suppression test (IST) to determine their steady-state plasma glucose (SSPG) as a direct measure of insulin sensitivity. SSPG exhibited a multimodal distribution suggesting the existence of subpopulations. The heterogeneous distribution of plasma glucose at 180 min (P = 0.011), with three modes, suggested differences in the plasma glucose level trajectories during the IST. Hence, the population was separated into three groups: (i) (n = 33), subjects with SSPG ≤ 152.5 mg/dl, corresponding to the first to fifth deciles; (ii) (n = 29), subjects in the interval 152.5 mg/dl < SSPG ≤ 300 mg/dl; (iii) (n = 7), subjects with SSPG > 300 mg/dl, corresponding to the tenth decile. Plasma glucose distributions at 180 min showed differences in their mean values and ranges among groups (P < 0.0001). The trajectories of the groups differed significantly during the IST (P < 0.0001). insulin sensitivity in our patients exhibited a discontinuous distribution, implying that PCOS is a heterogeneous disorder possessing subpopulations regarding IR.


1 November 1981 in The Journal of Clinical Endocrinology & Metabolism
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.C. Patricio H. Contreras
. Patricio H. Contreras
GGGladys Generini
Gladys Generini
HMHarold Michelsen
Harold Michelsen
HPHugo Pumarino
Hugo Pumarino
CCCarmen Campino
Carmen Campino
Although hyperprolactinemia and galactorrhea occur in primary hypothyroidism, factors influencing their presence are not well established. To further define these factors, the duration of illness and serum levels of PRL and TSH were investigated in a group of 50 patients with spontaneous (27 females and 7 males) and iatrogenic (16 females) primary hypothyroidism. To test the hypothesis of reduced hypothalamic dopamine content in overt long-standing primary hypothyroidism, the percent increase in serum PRL after the administration of metoclopramide, a dopamine blocker (2.5 mg, iv bolus), was studied in 13 women with spontaneous primary hypothyroidism and compared with that in 10 euthyroid women. While 88.2% of the patients with spontaneous primary hypothyroidism were hyperprolactinemic, only 31% of those with iatrogenic disease had elevated PRL levels. Women with spontaneous primary hypothyroidism had a longer duration of illness (72 ± 12 vs. 6.7 ± 1.8 months; P < 0.001) and higher serum TSH (189 ± 32 vs. 68 ± 14 μU/ml; P < 0.01) and PRL levels (49.8 ± 5.6 vs. 20.9 ± 0.8 ng/ml; P < 0.001) than women with iatrogenic hypothyroidism. A linear correlation existed between PRL and duration of illness (r = 0.53; P < 0.001), while a logarithmic correlation was found between PRL and TSH levels (r = 0.44; P < 0.01). Even though the duration of illness and TSH levels were similar in women with spontaneous disease with (n = 7) or without (n = 20) galactorrhea, the former were significantly younger (39.3 ± 1.8 vs. 56.6 ± 3 yr; P < 0.001), and their PRL levels were significantly higher (69.3 ± 8.9 vs. 42.9 ± 2.2 ng/ml; P < 0.001). The PRL response to metoclopramide in women with spontaneous disease was significantly smaller than that in controls (194 ± 39% vs. 446 ± 40%; P < 0.001) and inversely correlated with basal PRL levels (r = -0.55; P < 0.05). These data indicate that in primary hypothyroidism 1) the duration of illness is important in the development of hyperprolactinemia, 2) galactorrhea is more common in young women with spontaneous disease and high PRL levels, and 3) hypothalamic dopamine appears reduced in spontaneous disease.

26 June 2018 in Frontiers in Medicine
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.C. Patricio H. Contreras
. Patricio H. Contreras
FSFelipe G. Serrano
Felipe G. Serrano
ASAna M. Salgado
Ana M. Salgado
PVPilar Vigil
Pilar Vigil
A cohort of 141 males (18–80 yo, 42.9 ± 12.9) strongly suspected of being Insulin Resistant (IR) was prospectively studied by determining their insulin sensitivity (Pancreatic Suppression Test, PST) and testicular function (total testosterone and SHBG). The subjects were labeled as IR when the Steady State Plasma Glucose (SSPG) was ≥150 mg/dL and Non-Insulin Resistant (NIR) when SSPG was 3.0 ng/mL. Two out of three subjects turned out to be IR, while around one in four subjects were HYPOG. Contingency analysis indicated a significant interdependence between insulin resistance and hypogonadism (chi-square was 4.69, p = 0.0303). Age (>43 yo) predicted hypogonadism (AUROC 0.606, p = 0.0308). Twice as many HYPOG subjects were IR as compared with EUG subjects. Also, HYPOG subjects exhibited higher SSPG values as compared with EUG subjects. Statistically, neither Weight nor BMI predicted hypogonadism, while Waist Circumference (>110 cm) was only a mediocre predictor (AUROC 0.640, p = 0.009). SSPG (>224 mg/dL) on the other hand, was the best predictor of hypogonadism (AUROC 0.709, p = 0.002), outperforming Waist Circumference (half of the subjects with an SSPG >224 mg/dL were HYPOG). Age did not predict insulin resistance, while Weight (>99 kg), BMI (>29), and especially, Waist Circumference (>99 cm, AUROC 0.812, p < 0.0001) were all predictors of insulin resistance. Almost 90% of the subjects with a waist circumference >99 cm was IR. As a logical consequence of the selection criteria (various clues suggesting insulin resistance), most subjects with normal weight in this cohort were IR (53.3%) while 20% were HYPOG. On the other hand, 13.6% of the obese subjects were NIR, and 2 out of 3 of them were both NIR and EUG. In conclusion, Waist Circumference predicted both insulin resistance (>99 cm) and hypogonadism (>110 cm), suggesting that the first hit of abdominal obesity is insulin resistance and the second hit is male hypogonadism. Normal weight did not protect from IR, while a relevant proportion of obese subjects were NIR (with 2/3 being also EUG).