Jul 1, 1993

Active transport of benzylpenicillin across the blood-milk barrier

Pharmacology & Toxicology
A M Schadewinkel-ScherklH H Frey


Passage of benzylpenicillin across the mammary gland epithelium was studied both after systemic administration of benzylpenicillin in four goats and after intramammary infusion in three goats and two cows. The results after benzylpenicillin administration alone were compared with the results after combined administration of benzylpenicillin and probenecid. The studies on passage of benzylpenicillin through the blood-milk barrier showed, when milk to plasma ultrafiltrate ratios of benzylpenicillin were plotted versus time for each half of the udders, that active transport takes place from blood to milk during steady-state plasma concentrations. Active transport was demonstrated by inhibition with probenecid: (1) The entry of benzylpenicillin into milk was slowed down under the influence of probenecid. The AUC (area under the curve)-values during the first 30 min. were reduced by 66 +/- 9% compared with the AUC-values found without coadministration of probenecid. (2) In the presence of probenecid and during equilibrium between blood and milk concentrations, benzylpenicillin reached concentration ratios in the ultrafiltrates of milk and plasma which corresponded to those expected for diffusion alone. Without probenecid these ultra...Continue Reading

  • References8
  • Citations9


Mentioned in this Paper

Mammary Gland
Bos taurus
Process of Absorption
High Pressure Liquid Chromatography Procedure
Urea Measurement
Metabolic Inhibition
Capra hircus

About this Paper

Trending Feeds


Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Coronavirus Protein Structures

Deciphering and comparing the proteins of different coronaviruses forms a basis for understanding SARS-CoV-2 evolution and virus-receptor interactions. This feed follows studies analyzing the structures of coronavirus proteins, thereby revealing potential drug target sites.

DDX3X Syndrome

DDX3X syndrome is caused by a spontaneous mutation at conception that primarily affects girls due to its location on the X-chromosome. DDX3X syndrome has been linked to intellectual disabilities, seizures, autism, low muscle tone, brain abnormalities, and slower physical developments. Here is the latest research.

ALS: Stress Granules

Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative disease characterized by cytoplasmic protein aggregates within motor neurons. TDP-43 is an ALS-linked protein that is known to regulate splicing and storage of specific mRNAs into stress granules, which have been implicated in formation of ALS protein aggregates. Here is the latest research.

Fusion Oncoproteins in Childhood Cancers

This feed explores the function of fusion oncoproteins in specific childhood cancers, including those from racial/ethnic minority and underserved groups, and to provide preclinical assessment of potential therapeutics and how fusion oncoproteins influence gene expression to perturb normal cellular programs to block lineage differentiation and development

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Regulation of Vocal-Motor Plasticity

Dopaminergic projections to the basal ganglia and nucleus accumbens shape the learning and plasticity of motivated behaviors across species including the regulation of vocal-motor plasticity and performance in songbirds. Discover the latest research on the regulation of vocal-motor plasticity here.

Mitotic-exit networks with cytokinesis

Cytokinesis is the highly regulated process that physically separates daughter and mother cells in late mitosis. The mitotic-exit network (MEN), the signalling pathway that drives mitotic exit, directly regulates cytokinesis. Discover the latest research on mitotic-exit networks with cytokinesis here.

DNA Replication Origin

DNA replication is initiated as specific gene sequences, called origins, that function to start DNA replication. Pre-replication complexes are assembled at these origins during the G1 phase of the cell cycle. These sequences allow for targeted activation or deactivation of replication. Discover the latest research on DNA replication origins here.

Related Papers

Journal of Clinical Pharmacology
G P StoehrR H McDonald
The Clinical Investigator
I Kamilli, U Gresser
Biopharmaceutics & Drug Disposition
S K NiaziS I Ahmad
Journal of Human Lactation : Official Journal of International Lactation Consultant Association
P Anderson
Journal of Clinical Pharmacology
P ChaikinB K Silverman
© 2020 Meta ULC. All rights reserved