HCG – 5000ui

Researchers who buy HCG research material are typically studying human chorionic gonadotropin’s behavior as a functional analog of pituitary luteinizing hormone (LH), acting on the shared LH/chorionic-gonadotropin receptor (LHCGR). HCG is one of the compounds in this catalog with a long-completed FDA-approval pathway for pharmaceutical formulations, referenced here for research context only. The summary below reflects the published preclinical and clinical literature and is provided strictly for research and educational reference — it does not describe an intended effect of this product in humans or animals.

In this reference:

• What Is HCG?
• Proposed Mechanism of Action
• Chemical Identity
• Purity, Storage & Quality
• Research Applications
• What the Human Evidence Shows
• Frequently Asked Questions

What Is HCG?

Human chorionic gonadotropin (HCG) is a glycoprotein hormone normally produced by the placenta during pregnancy, structurally related to luteinizing hormone (LH), follicle-stimulating hormone (FSH), and thyroid-stimulating hormone. Researchers should be aware that pharmaceutical-grade HCG formulations (marketed under brand names including Pregnyl and Novarel) have long completed the FDA-approval pathway for specific fertility-medicine indications. That approval history is referenced here for research context only. This page describes the published pharmacology and endocrinology research literature on HCG as a molecule — it is entirely distinct from the research-use-only material sold on this page, which is not distributed, labeled, or intended as the approved pharmaceutical product.

Proposed Mechanism of Action

HCG acts as a functional analog of pituitary LH, binding the shared LH/chorionic-gonadotropin receptor (LHCGR), a G-protein-coupled receptor. Published research describes this receptor engagement as activating the canonical Gαs-coupled signaling pathway — stimulating adenylate cyclase, increasing intracellular cAMP, and activating protein kinase A (PKA) and the cAMP-sensor EPAC — which in tested models drives gonadal steroidogenesis, including testicular Leydig-cell androgen production in males.

A notable and actively studied finding in the pharmacology literature is that HCG and LH, despite sharing the same LHCGR receptor, do not produce identical downstream signaling: a controlled in vitro comparison reported that recombinant human HCG and recombinant human LH display biased agonism at the shared receptor, with HCG showing greater potency than LH in the specific cell models tested, and each ligand producing measurably different signaling kinetics and efficacy profiles (Riccetti L, et al., Sci Rep. 2017;7:940; PMID 28424471). This biased-agonism finding is a significant reason HCG continues to be studied as a distinct research tool from LH itself, rather than treated as functionally interchangeable.

Chemical Identity

Structure	Heterodimeric glycoprotein (alpha + beta subunits)
Molecular Weight	~36,700-40,000 g/mol
Receptor	LH/Chorionic Gonadotropin Receptor (LHCGR)
Appearance	White to off-white lyophilized powder

Purity, Storage & Quality

First Class Science supplies this HCG research material at research-grade purity, verified by independent third-party HPLC testing and mass spectrometry. A Certificate of Analysis is available for every batch at our Certificate of Analysis page, listing the specific lot’s purity result and test date.

Store the lyophilized (freeze-dried) compound at −20°C for long-term stability. This vial must be reconstituted with bacteriostatic or sterile water before laboratory use; after reconstitution, refrigerate at 2–8°C and use within 4–6 weeks. Avoid repeated freeze-thaw cycles and prolonged exposure to light or room-temperature conditions, both of which are associated with accelerated degradation in glycoprotein-hormone handling literature.

Important: This item is manufactured strictly for research purposes. It is not intended for human or veterinary use and is distributed solely for laboratory and scientific investigation.

Preparing Solutions for Laboratory Use

Laboratories reconstituting lyophilized HCG for in vitro or animal-model research typically follow standard glycoprotein-handling practice: the vial is brought to room temperature before opening, and a diluent — commonly reconstitution solution or sterile water for injection (SWFI) — is added slowly down the interior wall of the vial rather than directly onto the lyophilized material, to reduce foaming and mechanical stress. The vial is then gently swirled, never shaken, until fully dissolved.

Stock-solution concentration (typically expressed in international units, IU) for a given protocol is calculated by dividing the total activity in the vial by the volume of diluent added, and that calculation should be recorded in the study’s protocol documentation. This page describes general laboratory reconstitution practice for research use and is not a dosing guide for human or animal administration.

Quality Control Methodology

Each production batch of this HCG research material undergoes independent third-party testing before release. High-performance liquid chromatography (HPLC) confirms purity by measuring the proportion of the target glycoprotein relative to synthesis by-products or degradation fragments. Mass spectrometry separately supports molecular-identity confirmation. Both results are recorded on the batch’s published Certificate of Analysis, letting researchers independently verify identity and purity rather than relying on manufacturer claims alone.

Who Should Buy HCG Research Material

Researchers who buy HCG from First Class Science are typically university and academic laboratories, contract research organizations (CROs), and biotechnology R&D teams running in vitro LHCGR receptor-binding assays or animal-model studies on gonadal steroidogenesis and comparative LH/HCG signaling pharmacology. First Class Science requires that all research-material orders be placed by parties who acknowledge and agree to the research-use-only terms stated on this page prior to purchase.

Research Applications

The published literature on HCG spans several distinct research areas. Each is summarized below strictly as a description of what has been studied in animal, in vitro, or controlled clinical-trial models — not as a claim about effects for any individual using this product.

LHCGR Receptor Pharmacology and Biased-Agonism Research

The Riccetti et al. (2017) study cited above established that HCG and LH produce distinct signaling profiles at their shared receptor, a finding that continues to drive comparative structure-activity research on gonadotropin-receptor pharmacology.

Testicular Steroidogenesis Research

Animal-model research has examined HCG-driven Leydig-cell steroidogenesis, including receptor down-regulation kinetics following HCG administration and comparative studies against allosteric LH-receptor agonists in young, aging, and diabetic rat models.

Comparative Gonadotropin Signaling Research

Because HCG and LH share a receptor but differ in downstream signaling kinetics and potency, published research continues to use HCG as a comparative tool for studying gonadotropin-receptor signal transduction more broadly.

What the Human Evidence Shows

Researchers evaluating HCG should know that it has an extensive completed human clinical and pharmaceutical-development record — pharmaceutical-grade HCG formulations have been FDA-approved for decades for specific fertility-medicine indications, supported by a substantial clinical literature predating and extending beyond the specific molecular-pharmacology studies (such as Riccetti et al.) cited on this page.

That completed approval record relates specifically to pharmaceutical-grade HCG formulations manufactured and prescribed under an FDA-approved pathway for defined indications — it does not establish safety or efficacy for the research-grade HCG sold on this page, and does not support human self-administration of this research material outside the approved product and its prescribing context. Research-grade HCG as supplied here is not distributed, labeled, or intended as the approved pharmaceutical product, and this specific sale is not evaluated by the FDA.

Common Research Study Designs

Published studies referenced throughout this page typically fall into two designs: in vitro receptor-signaling assays comparing HCG and LH activity at the shared LHCGR receptor; and animal-model studies measuring steroidogenic response and receptor regulation following HCG administration. Understanding which design underlies a given finding — and which product (pharmaceutical vs. research-grade) it describes — is important context for interpreting the strength of any individual claim in the literature.

Frequently Asked Questions

What is the purity of this HCG research material?
Every batch is independently verified via third-party HPLC and mass-spectrometry testing, with a Certificate of Analysis published for each lot.

How should HCG research material be stored?
Store the lyophilized powder at −20°C. After reconstitution, refrigerate at 2–8°C and use within 4–6 weeks; avoid repeated freeze-thaw cycles.

Is HCG approved for human or animal use?
Distinct pharmaceutical-grade HCG formulations are FDA-approved for specific fertility-medicine indications. That approval applies to those specific prescribed products only — not to the research-grade HCG sold on this page, which is distributed strictly for laboratory research use and is not itself an approved product.

Has HCG been tested in humans at all?
Yes, extensively, in the pharmaceutical-development and clinical-fertility-medicine context described above. The specific molecular-pharmacology research cited on this page (PMID 28424471) is separate in vitro receptor-signaling research, not a clinical trial of this research-grade material.

What is the proposed mechanism of HCG in research models?
HCG binds the LH/chorionic-gonadotropin receptor (LHCGR), the same receptor LH activates, but published research shows the two ligands produce distinct (“biased”) downstream signaling profiles rather than identical effects.

What does the Certificate of Analysis show?
The Certificate of Analysis published for each batch shows the HPLC purity result and test date, allowing researchers to independently verify the identity and purity of the specific batch they receive.

Can HCG research material be shipped internationally?
Shipping availability and any import restrictions for research materials vary by destination country and are subject to change; researchers should confirm their local import regulations for research-use-only compounds before ordering.

Shipping, Handling & Compliance

This HCG research material ships as a lyophilized powder in a sealed glass vial, packaged to maintain cold-chain integrity in transit where applicable. All orders are subject to the research-use-only terms stated on this page, and First Class Science does not sell this or any other research material for human or veterinary administration under any circumstance.

Order tracking, batch-specific documentation requests, and general product questions can be directed to First Class Science customer support, which can confirm current lead times and any destination-specific documentation a receiving institution may require for its own compliance records.

Disclaimer: The research summarized above is drawn from third-party published studies conducted in animal or in vitro contexts. It is provided for research and educational reference only and does not describe an intended use, effect, or benefit of this product for any person or animal.

⊗ ALL ITEMS ARE SOLD FOR RESEARCH USE ONLY. This category covers strictly in vitro laboratory testing and scientific experimentation. Content on this site is for education only and does not authorize human or animal use of any kind, which is prohibited by law. Only trained, licensed professionals should handle these materials. Nothing sold here qualifies as a drug, food, or cosmetic, and none of it may be labeled, advertised, or used as such.